Methods and Apparatuses for COT Sharing in Unlicensed Spectrum

ABSTRACT

A user equipment (UE) may transmit a configured-grant uplink control information (CG-UCI) to a base station during a channel occupancy time (COT) initiated by the UE in a shared spectrum, the CG-UCI comprising COT sharing information, the COT sharing information indicating, at least, an index value corresponding to a combination of: an indication of an offset to a beginning of a downlink transmission opportunity during the COT; an indication of a duration of the downlink transmission opportunity during the COT; and an indication of a channel access priority class (CAPC) value used by the UE to initiate the COT. The base station may transmit a downlink transmission to the UE within the downlink transmission opportunity and in accordance with the COT sharing information in the transmitted CG-UCI. Apparatuses are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.17/036,517, filed on Sep. 29, 2020, and entitled “Methods andApparatuses for COT Sharing in Unlicensed Spectrum,” which claims thebenefit of U.S. Provisional Patent Application No. 62/911,161, filed onOct. 4, 2019, and entitled “Methods and Apparatuses for COT Sharing inUnlicensed Spectrum,” the entire contents of applications of which areincorporated by reference herein.

TECHNICAL FIELD

This disclosure relates generally to methods and apparatuses forconfigured-grant transmission, and more specifically to methods andapparatuses for channel occupancy time (COT) sharing in unlicensedspectrum.

BACKGROUND

In some wireless communication systems, a user equipment (UE) wirelesslycommunicates with a base station to send data to the base station and/orreceive data from the base station. A wireless communication from a UEto a base station is referred to as an uplink (UL) communication. Awireless communication from a base station to a UE is referred to as adownlink (DL) communication.

Resources are required to perform uplink and downlink communications.For example, a UE may wirelessly transmit data to a base station in anuplink transmission at a particular frequency and/or during a particularslot in time. The frequency and time slot used are examples ofresources.

In some wireless communication systems, if a UE wants to transmit datato a base station, the UE requests uplink resources from the basestation. The base station grants the uplink resources, and then the UEsends the uplink transmission using the granted uplink resources. Atransmission in such uplink resources granted by a base station isreferred to as a grant-based or scheduled UL transmission.

However, a UE may send uplink transmissions using certainsemi-statically configured uplink resources without specificallyrequesting use of the resources and without being dynamically granteduse of the resources by the base station. Such transmissions arereferred to as grant-free, grant-less, schedule-free, schedule-less, orconfigured-grant uplink transmissions. A UE sending a configured-grantuplink transmission, or configured to send a configured-grant uplinktransmission, may be referred to as operating in grant-free mode or inconfigured-grant mode.

One advantage of configured-grant transmission is lower latencyresulting from not having to request and receive a grant for anallocated time slot from a base station. Further, in a configured-granttransmission, scheduling overhead may be reduced. In a configured-grantscheme, the same uplink resources can be accessible to multipleconfigured-grant UEs served by the same base station.

There is a desire for configured-grant and sidelink transmission schemesthat can make more efficient use of available resources.

SUMMARY

According to one embodiment, there is disclosed a method performed by auser equipment (UE) for configured-grant transmission, the methodcomprising: transmitting, by the UE, a configured-grant uplink controlinformation (CG-UCI) to a base station during a channel occupancy time(COT) in an unlicensed spectrum, the CG-UCI comprising an indication ofa time delay to a beginning of a downlink transmission opportunityduring the COT; and receiving, by the UE, a downlink transmission withinthe downlink transmission opportunity.

In some embodiments, the CG-UCI further comprises an indication of aduration of the downlink transmission opportunity.

In some embodiments, the indication of the duration indicates, at least,a number of time slots of the downlink transmission opportunity.

In some embodiments, the CG-UCI comprises a value of an index, the valueof the index comprising the indication of the time delay and theindication of the duration.

In some embodiments, the value of the index indicates, at least, acombination in an ordered set of combinations of: time delays to thebeginning of the downlink transmission opportunity; and durations of thedownlink transmission opportunity.

In some embodiments, the indication of the time delay indicates, atleast, a number of time slots of the COT from transmission of the CG-UCIto the beginning of the downlink transmission opportunity.

In some embodiments, the indication of the time delay indicates, atleast, that the beginning of the downlink transmission opportunity is ina same time slot of the COT as an end of an uplink burst comprising thetransmission of the CG-UCI.

In some embodiments, the indication of the time delay indicates, atleast, that the beginning of the downlink transmission opportunity is ina same time slot of the COT as the transmission of the CG-UCI.

In some embodiments, the indication of the time delay comprises a valueof at least one bit in the CG-UCI indicating an end of the uplink burstcomprising the transmission of the CG-UCI.

In some embodiments, the indication of the time delay comprises a valueof an index, the value of the index comprising the indication of thetime delay, and some other values of the index identify respectivecombinations in an ordered set of combinations of: time delays to thebeginning of the downlink transmission opportunity; and durations of thedownlink transmission opportunity.

In some embodiments, the indication of the time delay indicates, atleast, a symbol of the beginning of the downlink transmissionopportunity.

In some embodiments, receiving the downlink transmission comprisesreceiving the downlink transmission from the base station.

In some embodiments, receiving the downlink transmission comprisesreceiving the downlink transmission in at least one physical downlinkshared channel (PDSCH).

In some embodiments, transmitting the CG-UCI to the base stationcomprises transmitting a physical uplink shared channel (PUSCH)comprising the CG-UCI.

In some embodiments, the COT was initiated by the UE.

In some embodiments, the COT was initiated by the UE in a channel accesspriority class (CAPC), and the CG-UCI further comprises an indication ofthe CAPC.

According to another embodiment, there is disclosed a user equipment(UE) apparatus comprising: at least one processor; and at least oneprocessor-readable storage device comprising stored thereonprocessor-executable instructions that, when executed by the at leastone processor, cause the at least one processor to, at least, executethe method.

According to another embodiment, there is disclosed a method performedby a base station for configured-grant transmission, the methodcomprising: receiving, by the base station, a configured-grant uplinkcontrol information (CG-UCI) from a user equipment (UE) during a channeloccupancy time (COT) in an unlicensed spectrum, the CG-UCI comprising anindication of a time delay to a beginning of a downlink transmissionopportunity during the COT; and transmitting, by the base station, adownlink transmission to the UE within the downlink transmissionopportunity.

In some embodiments, the CG-UCI further comprises an indication of aduration of the downlink transmission opportunity.

In some embodiments, the indication of the duration indicates, at least,a number of time slots of the downlink transmission opportunity.

In some embodiments, the CG-UCI comprises a value of an index, the valueof the index comprising the indication of the time delay and theindication of the duration.

In some embodiments, the value of the index indicates, at least, acombination in an ordered set of combinations of: time delays to thebeginning of the downlink transmission opportunity; and durations of thedownlink transmission opportunity.

In some embodiments, the indication of the time delay indicates, atleast, a number of time slots of the COT from transmission of the CG-UCIto the beginning of the downlink transmission opportunity.

In some embodiments, the indication of the time delay indicates, atleast, that the beginning of the downlink transmission opportunity is ina same time slot of the COT as an end of an uplink burst comprising thetransmission of the CG-UCI.

In some embodiments, the indication of the time delay indicates, atleast, that the beginning of the downlink transmission opportunity is ina same time slot of the COT as the transmission of the CG-UCI.

In some embodiments, the indication of the time delay comprises a valueof at least one bit in the CG-UCI indicating an end of the uplink burstcomprising the transmission of the CG-UCI.

In some embodiments, the indication of the time delay comprises a valueof an index, the value of the index comprising the indication of thetime delay, and some other values of the index identify respectivecombinations in an ordered set of combinations of: time delays to thebeginning of the downlink transmission opportunity; and durations of thedownlink transmission opportunity.

In some embodiments, the indication of the time delay indicates, atleast, a symbol of the beginning of the downlink transmissionopportunity.

In some embodiments, transmitting the downlink transmission comprisestransmitting the downlink transmission in at least one physical downlinkshared channel (PDSCH).

In some embodiments, receiving the CG-UCI comprises receiving a physicaluplink shared channel (PUSCH) comprising the CG-UCI.

In some embodiments, the COT was initiated by the UE.

In some embodiments, the COT was initiated by the UE in a channel accesspriority class (CAPC), and the CG-UCI further comprises an indication ofthe CAPC.

According to another embodiment, there is disclosed a base stationapparatus comprising: at least one processor; and at least oneprocessor-readable storage device comprising stored thereonprocessor-executable instructions that, when executed by the at leastone processor, cause the at least one processor to, at least, executethe method.

According to another embodiment, there is disclosed a method performedby a user equipment (UE) for configured-grant transmission, the methodcomprising transmitting, by the UE, a configured-grant uplink controlinformation (CG-UCI) to a base station during a channel occupancy time(COT) initiated by the UE in a shared spectrum, the CG-UCI comprisingCOT sharing information, the COT sharing information indicating, atleast, an index value corresponding to a combination of: an indicationof an offset to a beginning of a downlink transmission opportunityduring the COT; an indication of a duration of the downlink transmissionopportunity during the COT; and an indication of a channel accesspriority class (CAPC) value used by the UE to initiate the COT. Themethod further comprises receiving, by the UE, a downlink transmissionfrom the base station within the downlink transmission opportunity andin accordance with the COT sharing information in the transmittedCG-UCI.

In some embodiments, the indication of the duration indicates, at least,a number of time slots of the downlink transmission opportunity.

In some embodiments, the indication of the offset indicates, at least, anumber of time slots of the COT from transmission of the CG-UCI to thebeginning of the downlink transmission opportunity.

In some embodiments, receiving the downlink transmission comprisesreceiving the downlink transmission in at least one physical downlinkshared channel (PDSCH).

In some embodiments, transmitting the CG-UCI to the base stationcomprises transmitting a physical uplink shared channel (PUSCH)comprising the CG-UCI.

In some embodiments, the index value corresponds to a row of aconfigured table of COT sharing combinations, the row corresponding tothe combination, and at least one row of the configured table of COTsharing combinations indicates that COT sharing is not available.

In some embodiments, the index value corresponds to a row of aconfigured table of COT sharing combinations, the row corresponding tothe combination, and a bitwidth of the COT sharing information in theCG-UCI is ┌log_2

C┐ bits, where C is a number of combinations configured in the table.

In some embodiments, the method further comprises, after transmittingthe CG-UCI to the base station and before the beginning of the downlinktransmission opportunity, transmitting, by the UE, at least onesubsequent CG-UCI to the base station during the COT. In someembodiments, each subsequent CG-UCI of the at least one subsequentCG-UCI comprises COT sharing information indicating, at least, thedownlink transmission opportunity.

In some embodiments, transmitting the CG-UCI to the base stationcomprises transmitting the CG-UCI to the base station in an uplinkburst, and a switching gap between the uplink burst and the downlinktransmission is: 16 μs or 25 μs if a downlink listen-before talk (LBT)procedure after the uplink burst and before the downlink transmission isa category 2 (CAT2) downlink LBT procedure; and at most 16 μs if thedownlink LBT procedure is a category 1 (CAT1) downlink LBT procedurewithout LBT being performed in the switching gap.

According to another embodiment, there is disclosed a user equipment(UE) apparatus comprising at least one processor. The UE furthercomprises at least one processor-readable storage device comprisingstored thereon processor-executable instructions that, when executed bythe at least one processor, cause the at least one processor to, atleast, transmit a configured-grant uplink control information (CG-UCI)to a base station during a channel occupancy time (COT) initiated by theUE in a shared spectrum, the CG-UCI comprising COT sharing information,the COT sharing information indicating, at least, an index valuecorresponding to a combination of: an indication of an offset to abeginning of a downlink transmission opportunity during the COT; anindication of a duration of the downlink transmission opportunity duringthe COT; and an indication of a channel access priority class (CAPC)value used by the UE to initiate the COT. The processor-executableinstructions, when executed by the at least one processor, further causethe at least one processor to, at least, receive a downlink transmissionfrom the base station within the downlink transmission opportunity andin accordance with the COT sharing information in the transmittedCG-UCI.

In some embodiments, the indication of the duration indicates, at least,a number of time slots of the downlink transmission opportunity.

In some embodiments, the indication of the offset indicates, at least, anumber of time slots of the COT from transmission of the CG-UCI to thebeginning of the downlink transmission opportunity.

In some embodiments, the processor-executable instructions that, whenexecuted by the at least one processor, cause the at least one processorto receive the downlink transmission comprise processor-executableinstructions that, when executed by the at least one processor, causethe at least one processor to receive the downlink transmission in atleast one physical downlink shared channel (PDSCH).

In some embodiments, the processor-executable instructions that, whenexecuted by the at least one processor, cause the at least one processorto transmit the CG-UCI to the base station comprise processor-executableinstructions that, when executed by the at least one processor, causethe at least one processor to transmit a physical uplink shared channel(PUSCH) comprising the CG-UCI.

In some embodiments, the index value corresponds to a row of aconfigured table of COT sharing combinations, the row corresponding tothe combination, and at least one row of the configured table of COTsharing combinations indicates that COT sharing is not available.

In some embodiments, the index value corresponds to a row of aconfigured table of COT sharing combinations, the row corresponding tothe combination, and a bitwidth of the COT sharing information in theCG-UCI is ┌log_2

C┐ bits, where C is a number of combinations configured in the table.

In some embodiments, the processor-executable instructions, whenexecuted by the at least one processor, further cause the at least oneprocessor to, at least, after transmitting the CG-UCI to the basestation and before the beginning of the downlink transmissionopportunity, transmit at least one subsequent CG-UCI to the base stationduring the COT. In some embodiments, each subsequent CG-UCI of the atleast one subsequent CG-UCI comprises COT sharing informationindicating, at least, the downlink transmission opportunity.

In some embodiments, the processor-executable instructions that, whenexecuted by the at least one processor, cause the at least one processorto transmit the CG-UCI to the base station comprise processor-executableinstructions that, when executed by the at least one processor, causethe at least one processor to transmit the CG-UCI to the base station inan uplink burst such that a switching gap between the uplink burst andthe downlink transmission is: 16 μs or 25 μs if a downlink listen-beforetalk (LBT) procedure after the uplink burst and before the downlinktransmission is a category 2 (CAT2) downlink LBT procedure; and at most16 μs if the downlink LBT procedure is a category 1 (CAT1) downlink LBTprocedure without LBT being performed in the switching gap.

According to another embodiment, there is disclosed a method performedby a base station for configured-grant transmission, the methodcomprising receiving, by the base station, a configured-grant uplinkcontrol information (CG-UCI) from a user equipment (UE) during a channeloccupancy time (COT) initiated by the UE in a shared spectrum, theCG-UCI comprising COT sharing information, the COT sharing informationindicating, at least, an index value corresponding to a combination of:an indication of an offset to a beginning of a downlink transmissionopportunity during the COT; an indication of a duration of the downlinktransmission opportunity during the COT; and an indication of a channelaccess priority class (CAPC) value used by the UE to initiate the COT.The method further comprises transmitting, by the base station, adownlink transmission to the UE within the downlink transmissionopportunity and in accordance with the COT sharing information in thetransmitted CG-UCI.

In some embodiments, the indication of the duration indicates, at least,a number of time slots of the downlink transmission opportunity.

In some embodiments, the indication of the offset indicates, at least, anumber of time slots of the COT from detection of the CG-UCI to thebeginning of the downlink transmission opportunity.

In some embodiments, transmitting the downlink transmission comprisestransmitting the downlink transmission in at least one physical downlinkshared channel (PDSCH).

In some embodiments, receiving the CG-UCI comprises receiving a physicaluplink shared channel (PUSCH) comprising the CG-UCI.

In some embodiments, the index value corresponds to a row of aconfigured table of COT sharing combinations corresponding to thecombination, and at least one row of the configured table of COT sharingcombinations indicates that COT sharing is not available.

In some embodiments, the index value corresponds to a row of aconfigured table of COT sharing combinations corresponding to thecombination, and a bitwidth of the COT sharing information in the CG-UCIis ┌log_2

C┐ bits, where C is a number of combinations configured in the table.

In some embodiments, the method further comprises, after receiving theCG-UCI and before the beginning of the downlink transmissionopportunity, receiving, by the base station, at least one subsequentCG-UCI from the UE during the COT. In some embodiments, each subsequentCG-UCI of the at least one subsequent CG-UCI comprises the COT sharinginformation indicating, at least, the downlink transmission opportunity.

In some embodiments, receiving the CG-UCI comprises receiving the CG-UCIin an uplink burst, and a switching gap between the uplink burst and thedownlink transmission is: 16 μs or 25 μs if a downlink listen-beforetalk (LBT) procedure after the uplink burst and before the downlinktransmission is a category 2 (CAT2) downlink LBT procedure; and at most16 μs if the downlink LBT procedure is a category 1 (CAT1) downlink LBTprocedure without LBT being performed in the switching gap.

According to another embodiment, there is disclosed a base stationapparatus comprising at least one processor. The base station furthercomprises at least one processor-readable storage device comprisingstored thereon processor-executable instructions that, when executed bythe at least one processor, cause the at least one processor to, atleast, receive a configured-grant uplink control information (CG-UCI)from a user equipment (UE) during a channel occupancy time (COT)initiated by the UE in a shared spectrum, the CG-UCI comprising COTsharing information, the COT sharing information indicating, at least,an index value corresponding to a combination of: an indication of anoffset to a beginning of a downlink transmission opportunity during theCOT; an indication of a duration of the downlink transmissionopportunity during the COT; and an indication of a channel accesspriority class (CAPC) value used by the UE to initiate the COT. Theprocessor-executable instructions, when executed by the at least oneprocessor, further cause the at least one processor to, at least,transmit a downlink transmission to the UE within the downlinktransmission opportunity and in accordance with the COT sharinginformation in the transmitted CG-UCI.

In some embodiments, the indication of the duration indicates, at least,a number of time slots of the downlink transmission opportunity.

In some embodiments, the indication of the offset indicates, at least, anumber of time slots of the COT from transmission of the CG-UCI to thebeginning of the downlink transmission opportunity.

In some embodiments, the processor-executable instructions that, whenexecuted by the at least one processor, cause the at least one processorto transmit the downlink transmission comprise processor-executableinstructions that, when executed by the at least one processor, causethe at least one processor to transmit the downlink transmission in atleast one physical downlink shared channel (PDSCH).

In some embodiments, the processor-executable instructions that, whenexecuted by the at least one processor, cause the at least one processorto receive the CG-UCI comprise processor-executable instructions that,when executed by the at least one processor, cause the at least oneprocessor to receive a physical uplink shared channel (PUSCH) comprisingthe CG-UCI.

In some embodiments, the index value corresponds to a row of aconfigured table of COT sharing combinations, the row corresponding tothe combination, and at least one row of the configured table of COTsharing combinations indicates that COT sharing is not available.

In some embodiments, the index value corresponds to a row of aconfigured table of COT sharing combinations, the row corresponding tothe combination, and a bitwidth of the COT sharing information in theCG-UCI is ┌log_2

C┐ bits, where C is a number of combinations configured in the table.

In some embodiments, the processor-executable instructions, whenexecuted by the at least one processor, further cause the at least oneprocessor to, at least, after receiving the CG-UCI and before thebeginning of the downlink transmission opportunity, receive at least onesubsequent CG-UCI from the UE during the COT. In some embodiments, eachsubsequent CG-UCI of the at least one subsequent CG-UCI comprises theCOT sharing information indicating, at least, the downlink transmissionopportunity.

In some embodiments, the processor-executable instructions that, whenexecuted by the at least one processor, cause the at least one processorto receive the CG-UCI comprise processor-executable instructions that,when executed by the at least one processor, cause the at least oneprocessor to receive the CG-UCI in an uplink burst such that a switchinggap between the uplink burst and the downlink transmission is: 16 μs or25 μs if a downlink listen-before talk (LBT) procedure after the uplinkburst and before the downlink transmission is a category 2 (CAT2)downlink LBT procedure; and at most 16 μs if the downlink LBT procedureis a category 1 (CAT1) downlink LBT procedure without LBT beingperformed in the switching gap.

Other aspects and features will become apparent to those ordinarilyskilled in the art upon review of the following description ofillustrative embodiments in conjunction with the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a communication system according to oneembodiment.

FIG. 2A is a schematic illustration of a user equipment (UE) of thecommunication system of FIG. 1 .

FIG. 2B is a schematic illustration of a base station of thecommunication system of FIG. 1 .

FIGS. 3-10 are schematic illustrations of examples of time resources forconfigured grant by the UE of FIG. 2A in an unlicensed spectrum in acell of the base station of FIG. 2B according to various embodiments.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

For illustrative purposes, specific example embodiments will beexplained in greater detail below in conjunction with the figures. Itshould be appreciated, however, that the present disclosure providesmany applicable concepts that can be embodied in a wide variety ofspecific contexts. The specific embodiments discussed are merelyillustrative and do not limit the scope of the present disclosure.

In this disclosure, configured-grant transmissions refer to datatransmissions that are performed without communicating grant-basedsignaling in a dynamic control channel, such as a physical downlinkcontrol channel (PDCCH). Configured-grant transmissions can includeuplink or downlink transmissions, and may encompass Semi-PersistentlyScheduled (SPS) transmissions, and should be interpreted as such unlessotherwise specified.

Communication System

FIG. 1 illustrates an example communication system 100. In general, thesystem 100 enables multiple wireless or wired user devices to transmitand receive data and other content. The system 100 may implement one ormore channel access methods, such as code division multiple access(CDMA), time division multiple access (TDMA), frequency divisionmultiple access (FDMA), orthogonal FDMA (OFDMA), or single-carrier FDMA(SC-FDMA).

In this example, the communication system 100 includes electronicdevices (EDs) or user equipments (UEs) 110 a-110 c, radio accessnetworks (RANs) 120 a-120 b, a core network 130, a public switchedtelephone network (PSTN) 140, the Internet 150, and other networks 160.While certain numbers of these components or elements are shown in FIG.1 , any number of these components or elements may be included in thesystem 100.

The UEs 110 a-110 c are configured to operate and/or communicate in thesystem 100. For example, the UEs 110 a-110 c are configured to transmitand/or receive via wireless or wired communication channels. Each UE 110a-110 c represents any suitable end user device and may include suchdevices (or may be referred to) as a user equipment/device (UE),wireless transmit/receive unit (WTRU), mobile station, fixed or mobilesubscriber unit, cellular telephone, personal digital assistant (PDA),smartphone, laptop, computer, touchpad, wireless sensor, or consumerelectronics device.

The RANs 120 a-120 b include base stations 170 a-170 b, respectively.Each base station 170 a-170 b is configured to interface wirelessly withone or more of the UEs 110 a-110 c to enable access to a backhaulnetwork. The backhaul network in FIG. 1 includes the core network 130,the PSTN 140, the Internet 150, and/or the other networks 160. Forexample, the backhaul network can include a 5G communication systemnetwork or a future next evolution system network. For example, the basestations 170 a-170 b may include (or be) one or more of a basetransceiver station (BTS), a Node-B (NodeB), an evolved NodeB (eNodeB),a gigabit NodeB (gNodeB), a Home NodeB, a Home eNodeB, a Home gNodeB, asite controller, an access point (AP), or a wireless router. The UEs 110a-110 c are configured to interface and communicate with the Internet150 and may access the core network 130, the PSTN 140, and/or the othernetworks 160.

In the embodiment shown in FIG. 1 , the base station 170 a forms part ofthe RAN 120 a, which may include other base stations, elements, and/ordevices. Also, the base station 170 b forms part of the RAN 120 b, whichmay include other base stations, elements, and/or devices. The basestation 170 a operates to transmit and/or receive wireless signalswithin a particular coverage area or cell 175 a, and the base station170 b operates to transmit and/or receive wireless signals within aparticular coverage area or cell 175 b. In some embodiments,multiple-input multiple-output (MIMO) technology may be employed havingmultiple transceivers for each cell.

The base stations 170 a-170 b communicate with one or more of the UEs110 a-110 c over one or more air interfaces 190 using wirelesscommunication links. The air interfaces 190 may utilize any suitableradio access technology.

It is contemplated that the system 100 may use multiple channel accessfunctionality, including such schemes as described above. In particularembodiments, the base stations and UEs implement 3G, long-term evolution(LTE), LTE-A, LTE-B, and/or 5G. Of course, other multiple access schemesand wireless protocols may be utilized.

The RANs 120 a-120 b are in communication with the core network 130 toprovide the UEs 110 a-110 c with voice, data, application, voice overinternet protocol (VoIP), or other services. The RANs 120 a-120 b and/orthe core network 130 may be in direct or indirect communication with oneor more other RANs (not shown). The core network 130 may also serve as agateway access for other networks (such as the PSTN 140, the Internet150, and the other networks 160). In addition, some or all of the UEs110 a-110 c may include functionality for communicating with differentwireless networks over different wireless links using different wirelesstechnologies and/or protocols. Instead of wireless communication (or inaddition thereto), the UEs 110 a-110 c may communicate via wiredcommunication channels to a service provider or switch (not shown), andto the internet 150.

Although FIG. 1 illustrates one example of a communication system,various changes may be made to FIG. 1 . For example, the communicationsystem 100 could include any number of UEs, base stations, networks, orother components in any suitable configuration.

FIGS. 2A and 2B illustrate example devices that may implement themethods and teachings according to this disclosure. In particular, FIG.2A illustrates an example UE 110 corresponding to any of the UEs 110a-110 c, and FIG. 2B illustrates an example base station 170corresponding to either of the base stations 170 a-170 b. Thesecomponents could be used in the system 100 or in any other suitablesystem.

As shown in FIG. 2A, the UE 110 includes at least one processing unit200. The processing unit 200 implements various processing operations ofthe UE 110. For example, the processing unit 200 could perform signalcoding, data processing, power control, input/output processing, or anyother functionality enabling the UE 110 to operate in the system 100.The processing unit 200 also supports the methods and teachingsdescribed in more detail below. Each processing unit 200 includes anysuitable processing or computing device configured to perform one ormore operations. Each processing unit 200 could, for example, include amicroprocessor, microcontroller, digital signal processor, fieldprogrammable gate array, or an application-specific integrated circuit.

The UE 110 also includes at least one transceiver 202. The transceiver202 is configured to modulate data or other content for transmission byat least one antenna 204 or network interface controller (NIC). Thetransceiver 202 is also configured to demodulate data or other contentreceived by the at least one antenna 204. Each transceiver 202 includesany suitable structure for generating signals for wireless or wiredtransmission and/or processing signals received wirelessly or by wire.Each antenna 204 includes any suitable structure for transmitting and/orreceiving wireless or wired signals. One or multiple transceivers 202could be used in the UE 110, and one or multiple antennas 204 could beused in the UE 110. Although shown as a single functional unit, atransceiver 202 could also be implemented using at least one transmitterand at least one separate receiver.

The UE 110 further includes one or more input/output devices 206 orinterfaces (such as a wired interface to the Internet 150). Theinput/output devices 206 facilitate interaction with a user or otherdevices (network communications) in the network. Each input/outputdevice 206 includes any suitable structure for providing information toor receiving/providing information from a user, such as a speaker,microphone, keypad, keyboard, display, or touch screen, includingnetwork interface communications.

In addition, the UE 110 includes at least one memory 208. The memory 208stores instructions and data used, generated, or collected by the UE110. For example, the memory 208 could store software or firmwareinstructions executed by the processing unit(s) 200 and data used toreduce or eliminate interference in incoming signals. Each memory 208includes any suitable volatile and/or non-volatile storage and retrievaldevice(s). Any suitable type of memory may be used, such asrandom-access memory (RAM), read-only memory (ROM), hard disk, opticaldisc, subscriber identity module (SIM) card, memory stick, securedigital (SD) memory card, and the like.

As shown in FIG. 2B, the base station 170 includes at least oneprocessing unit 250, at least one transmitter 252, at least one receiver254, one or more antennas 256, at least one memory 258, and one or moreinput/output devices or interfaces 266. A scheduler, which would beunderstood by one skilled in the art, could also be coupled to theprocessing unit 250. The scheduler could be included within or operatedseparately from the base station 170. The processing unit 250 implementsvarious processing operations of the base station 170, such as signalcoding, data processing, power control, input/output processing, or anyother functionality. The processing unit 250 can also support themethods and teachings described in more detail below. Each processingunit 250 includes any suitable processing or computing device configuredto perform one or more operations. Each processing unit 250 could, forexample, include a microprocessor, microcontroller, digital signalprocessor, field programmable gate array, or application specificintegrated circuit.

Each transmitter 252 includes any suitable structure for generatingsignals for wireless or wired transmission to one or more UEs or otherdevices. Each receiver 254 includes any suitable structure forprocessing signals received wirelessly or by wire from one or more UEsor other devices. Although shown as separate transmitter 252 andreceiver 254, these two devices could be combined as a transceiver. Eachantenna 256 includes any suitable structure for transmitting and/orreceiving wireless or wired signals. While a common antenna 256 is shownhere as being coupled to the transmitter 252, one or more antennas 256could be coupled to the receiver 252, allowing separate antennas 256 tobe coupled to the transmitter and the receiver as separate components.Each memory 258 includes any suitable volatile and/or non-volatilestorage and retrieval device(s). Each input/output device 266facilitates interaction with a user or other devices (networkcommunications) in the network. Each input/output device 266 includesany suitable structure for providing information to orreceiving/providing information from a user, including network interfacecommunications.

Configured-Grant Transmissions

The base stations 170 are configured to support wireless communicationwith the UEs 110 a-110 c, which may each send configured-grant uplinktransmissions. The UEs 110 a-110 c may be configured forconfigured-grant transmission, for example by configured-grant resourcepre-configuration at the UE connection setup or by configured-grantresource configuration or re-configuration from an update duringoperation. For example, configured-grant resources can be configured forUEs by broadcast or multi-cast signaling in some embodiments. Two ormore configured-grant transmissions can share the same configuredresources. Furthermore, a grant-based transmission can use dedicatedresources or can share resources (fully or partially) withconfigured-grant resources in a time interval.

Any of the configured-grant and grant-based transmissions may, in someembodiments, be used for any application traffic or services type,depending on the associated application requirements and quality ofservice (QoS). Configured-grant transmission can be used, for example,for: ultra-reliable low latency communication (URLLC) traffic to satisfythe low latency requirement; enhanced mobile broadband (eMBB) trafficwith short packets to save signaling overhead; and eMBB traffic toenhance resource utilization and spectrum efficiency.

A numerology is defined as a set of physical-layer parameters of an airinterface that are used to communicate a particular signal. Fororthogonal frequency-division multiplexing (OFDM)-based communication, anumerology may be described in terms of at least subcarrier spacing(SCS) and OFDM symbol duration, and may also be defined by otherparameters such as fast Fourier transform (FFT) and/or inverse FFT(IFFT) length, transmission time slot length, and cyclic prefix (CP)length or duration. In general, numerologies used for configured-grantUL transmissions in the unlicensed spectrum in accordance with thepresent disclosure may be selected so as to support certainfunctionality.

One UE or a group of UEs may have a group identifier (ID) or radionetwork temporary ID (RNTI) to share the same parameter or resourceconfiguration, and an RNTI may be a grant-free RNTI (GF-RNTI) or agrant-based RNTI (GB-RNTI). The group ID can be pre-configured, ordynamically configured to each UE. The parameter or resourceconfiguration to the UE(s) with the group ID can be done by semi-staticor dynamic signaling, for example. The group ID can be used for resourcedeactivation or activation for the UEs in the group, for example. Theresources being activated or deactivated can include frequency, time,and reference signal (RS) associated with each UE in the group.

The associated resources configured for a UE or a group of UEs caninclude any or all of the following.

-   -   1) Frequency resources in a transmission time interval (TTI),        e.g. a symbol, mini-slot or slot. In one example, a physical        resource block (PRB) scheme is provided. The PRB scheme        indicates physical starting frequency resource block (RB) and        size of the RB allocation. For UL transmission in an unlicensed        cell in particular, the PRB scheme may alternatively indicate        one or more frequency interlaces selected from a set of        frequency interlaces pre-defined over the unlicensed cell or a        bandwidth part (BWP) thereof. If the BWP is a wideband (WB) BWP,        i.e., comprises more than one contiguous unlicensed channel        (also known as sub-bands), the PRB scheme may further indicate        either a sub-band index or a starting PRB and a size of the RB        allocation within the one or more frequency interlaces.    -   2) Time resources, including starting/ending position of one        data transmission time interval. For example, TTI can be one        symbol, mini-slot, or slot.    -   3) Reference signal (RS) or RS configuration, where each UE can        be configured with one or more reference signals (RSs) e.g.        demodulation reference signals (DMRSs) depending on scenarios        involved. For a group of UEs, each UE may or may not have a        different RS or have a different set of RSs. Note that different        RSs can be orthogonal or non-orthogonal to each other depending        on an application, e.g., such as URLLC application or massive        machine-type communication (mMTC) application.    -   4) One or more hybrid automatic repeat request (HARQ) process        IDs per UE.    -   5) One or more modulation and coding schemes (MCSs) per UE,        where a grant-free UE can indicate explicitly or implicitly        which MCS to use for a transmission.    -   6) Number of grant-free transmission repetitions K, one or more        K values can be configured for a UE, where which K value to use        depends on certain rule taking into account UE channel        conditions, service types, etc.    -   7) Power control parameters, including power ramping step size        (e.g., for a UE).    -   8) Other parameters, including information associated with        general grant-based data and control transmissions. Note that        sometimes, a subset of grant-free resources can be referred to        as “fixed” or “reserved” resources; whereas a subset of        grant-based resources can be referred to as “flexible”        resources, which can be dynamically scheduled by a base station.

One type of transmission with configured grant (TCG) for new radio (NR),referred to as Type 1 NR TCG, includes using radio resource control(RRC) signaling to provide configuration information to a UE. Examplesof configuration information include, but are not limited to,periodicity, offset, time-frequency allocation, UE-specific demodulationreference signals (DMRS) configuration, modulation codingscheme/transmit block size (MCS/TBS), number of repetitions (K), andpower control.

In a second type, referred to as Type 2 NR TCG, RRC signaling can beused to provide a UE some of the configuration information, and otherconfiguration information is provided to the UE in activation downlinkcontrol information (DCI). Examples of the configuration informationthat might be provided in RRC signaling include, but are not limited to,periodicity, power control, number of repetitions (K), and MCS/TBS.Examples of configuration information that may be provided in theactivation DCI include, but are not limited to, offset, time-frequencyallocation, MCS/TBS and UE-specific DMRS configuration information.

With regard to time-domain resource allocation for the configured granttransmission in unlicensed spectrum, the following two parameters areconfigured through RRC signaling for both Type 1 and Type 2 identifiedabove.

-   -   K-repetition: K={1, 2, 4, 8} consecutive transmissions of the        same transmit block (TB) on the resources configured for        transmission of the physical uplink shared channel (PUSCH). For        the operation of NR in the unlicensed spectrum (NR-U), the K        repetitions of the same TB may or may not occur on consecutive        CG PUSCH resources.    -   Periodicity: The following periodicities are supported depending        on the configured subcarrier spacing:        -   15 kHz: 2, 7, n×14, where n∈{1, 2, 4, 5, 8, 10, 16, 20, 32,            40, 64, 80, 128, 160, 320, 640};        -   30 kHz: 2, 7, n×14, where n∈{1, 2, 4, 5, 8, 10, 16, 20, 32,            40, 64, 80, 128, 160, 256, 320, 640, 1280};        -   60 kHz with normal CP: 2, 7, n×14, where n∈{1, 2, 4, 5, 8,            10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 512, 640,            1280, 2560}; and        -   60 kHz with extended cyclic prefix (ECP): 2, 6, n×12, where            n∈{1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256,            320, 512, 640, 1280, 2560}.

The following two parameters are configured via RRC for Type 1 and viaactivation DCI for Type 2:

-   -   timeDomainAllocation: Allocation of configured uplink grant in        time domain which indicates a table entry containing        startSymbolAndLength; and    -   timeDomainOffset: Offset of a resource with respect to SFN=0 in        time domain for Type 1, and with respect to the transmission        timing of the activation DCI for Type 2.

Unlicensed Spectrum

Given the scarcity and expense of bandwidth in the licensed spectrum,and the increasing demand for data transmission capacity, there isincreasing interest in offloading at least some communication traffic,such as uplink communication traffic, to the unlicensed spectrum, whichmay be equivalent to a “shared spectrum”. For example, there has beensignificant interest in the unlicensed 5 GHz spectrum in which manyWireless Local Area Networks (WLANs) operate. Accordingly, in order tooperate in this spectrum, efficient and fair coexistence with WLANs,along with compliance with region-specific unlicensed spectrumregulations, may be necessary.

Before a UE can access unlicensed spectrum to transmit on an unlicensedspectrum sub-band, the UE performs a listen-before talk (LBT) operation(for example including initial clear channel assessment (ICCA) and anextended clear channel assessment (ECCA)) in order to check that thechannel is idle before transmitting. A sub-band of an unlicensedspectrum band may include a group of frequency resources that includesone or more unlicensed channels as defined by the IEEE 802.11 standardin the geographical region of operation, or one or more bandwidth parts(BWPs) as defined by 3GPP standards, for example.

In regions such as Europe and Japan, devices attempting to access theunlicensed spectrum have to comply with either a load-based equipment(LBE) LBT procedure or a frame-based equipment (FBE) LBT procedure.

In the LBE LBT procedure, a device attempting to access the unlicensedspectrum can start transmitting at an arbitrary time after a successfulclear channel assessment (CCA). The CCA mechanism employed in such LBELBT procedures may be the same CCA mechanism employed in WLAN, i.e.carrier sense multiple access with collision avoidance (CSMA/CA), or itmay be based on an energy-detection-based CCA. For example, anenergy-detection-based CCA may utilize a random back-off to determinethe size of a contention window, and a respective maximum channeloccupancy time (MCOT) that determines the maximum amount of time that adevice may occupy in the unlicensed channel once it has successfullycontended for a transmission opportunity.

In FBE LBT procedures, a device attempting to access the unlicensedspectrum can start transmitting only at periodic instants after a shortsuccessful energy-detection-based CCA. The minimum time between suchperiodic instants is the fixed frame period, which encompasses thechannel occupancy time of the transmission and an idle period. Under theregulatory requirements, the channel occupancy may be between 1 and 10milliseconds (ms) and the idle period must be at least 5% of the channeloccupancy time and lower bounded by 100 microseconds (μs). In addition,under the regulatory requirements, devices employ anenergy-detection-based CCA in which a channel is determined to be busyif the total energy detected in the channel is greater than a CCAthreshold value that is upper bounded by a function of the transmitpower of the device. In particular, the upper bound of the CCA thresholdhas been regulated as follows:

-   -   CCA Threshold≥−73 dBm/MHz+(23−max Tx EIRP) [dBm],        where max Tx EIRP is a device's maximum transmit equivalent        isotropically radiated power (EIRP). As a result, the higher the        max Tx power and/or the antenna gain, the lower the CCA        threshold that is allowed. Under the current regulatory        requirements, the CCA period must be at least 9 microseconds        (μs) long, with 25 μs being typical.

If individual UEs accessed the unlicensed spectrum individually withoutcoordination, it could create delay and potentially deteriorateperformance. For example, If UEs perform independent LBT procedures,they may either start transmitting uplink data or send a reservationsignal to ensure that other devices do not occupy an unlicensed channelbefore they are able to transmit. In both situations, if no coordinationexists between UEs in terms of aligning their CCAs, sending of thereservation signals or starting of their uplink transmissions, then thechannel may appear to be busy for other UEs, which can increase thelatency of uplink transmission for those other UEs.

Configured-Grant Uplink Control Information

FIG. 3 illustrates an example of a time resource 300 for configuredgrant transmission by the UE 110 a in an unlicensed spectrum in the cell175 a of the base station 170 a according to one embodiment, althoughalternative embodiments may involve different UEs, different cells,and/or different base stations.

In the example of FIG. 3 , the time resource 300 includes five timeslots 302, 304, 306, 308, and 310. The UE 110 a attempted to initiatechannel occupancy time (COT) for an uplink transmission to the basestation 170 a in the time resource 300 by a first uplink (UL) LBTprocedure 312 at the beginning of the time slot 302. In this example,the first UL LBT procedure 312 failed because of a “busy” assessment.The UE 110 a attempted again to initiate COT for an uplink transmissionto the base station 170 a in the time resource 300 by proceeding with asecond UL LBT procedure 316 towards the next potential PUSCH, thestarting point of which is after a delay 314 from the beginning of thetime slot 302. In the embodiment shown, the first UL LBT procedure 312and the second UL LBT procedure 316 are category 4 (CAT4) UL LBTprocedures that involve a random back-off, but in alternativeembodiments, a UE may attempt to initiate COT using other procedures.

In this example, the second UL LBT procedure 316 was successful, and theUE 110 a initiated COT having a MCOT 318 of four time slots 320, 322,324, and 326 in the time resource 300. The COT in the MCOT 318 istherefore a COT initiated by the UE 110 a. During the COT in the MCOT318, the UE 110 a transmits an uplink transmission to the base station170 a in a physical uplink shared channel (PUSCH) 328 in the time slot302, in a PUSCH 330 in the time slot 304, and in a PUSCH 332 in the timeslot 304. The PUSCHs 328, 330, and 332 therefore form an uplink burst334 in an uplink transmission from the UE 110 a to the base station 170a in the time resource 300 in the unlicensed spectrum in the cell 175 aof the base station 170 a.

However, in this example, the uplink burst 334 does not extend into thetime slots 306 and 308 that are within the MCOT 318. Therefore, theuplink burst 334 includes indications of a downlink transmissionopportunity 336 (or, more generally, a transmission opportunity) in thetime slots 306 and 308 during the COT in the MCOT 318. The downlinktransmission opportunity 336 begins two time slots after the time slot302, which is one time slot after the time slot 304, and has a durationof two time slots 306 and 308.

In this example, the PUSCH 328 in the time slot 302 includes aconfigured-grant uplink control information (CG-UCI) 338. In general, aCG-UCI as described herein may include one or more of: a HARQ ID, a newdata indicator (NDI), a redundancy version (RV), COT sharing informationas described below, or other information such as a UE ID.

The COT sharing information of the CG-UCI 338 includes an indicationthat the downlink transmission opportunity 336 begins two time slotsafter the time slot 302, indicated by l=2 in FIG. 3 . More generally, lis a “DL offset” that may indicate a number of time slots of COT fromtransmission of the CG-UCI 338 to the beginning of the downlinktransmission opportunity 336. The COT sharing information of the CG-UCI338 also includes an indication that the downlink transmissionopportunity 336 has a duration of two time slots, indicated by d=2 inFIG. 3 . More generally, d may indicate a duration of the downlinktransmission opportunity 336 as a number of time slots of the downlinktransmission opportunity 336. In general, an indication in a CG-UCI asdescribed herein may be an indication encoded in one or more bit fieldsof the CG-UCI.

Further, in this example, the PUSCH 330 in the time slot 304 includes aCG-UCI 340, and the COT sharing information of the CG-UCI 340 includesan indication that the downlink transmission opportunity 336 begins onetime slot after the time slot 304, indicated by the DL offset l=1 inFIG. 3 . The COT sharing information of the CG-UCI 340 also includes anindication that the downlink transmission opportunity 336 has a durationof two time slots, again indicated by d=2 in FIG. 3 . Further, in thisexample, the PUSCH 332 in the time slot 304 includes a CG-UCI 342, andthe COT sharing information of the CG-UCI 342 includes an indicationthat the downlink transmission opportunity 336 begins one time slotafter the time slot 304, again indicated by l=1 in FIG. 3 . The COTsharing information of the CG-UCI 338 also includes an indication thatthe downlink transmission opportunity 336 has a duration of two timeslots, again indicated by d=2 in FIG. 3 . The values of l and d in theembodiment of FIG. 3 are examples only. Alternative embodiments mayinclude different indications of a time delay (or offset) to a beginningof a downlink transmission opportunity, and alternative embodiments mayinclude different indications of a duration of the downlink transmissionopportunity.

Therefore, more generally, the COT sharing information of each of theCG-UCIs 338, 340, and 342 identifies the downlink transmissionopportunity 336 to the base station 170 a to allow the base station 170a to share the COT in the MCOT 318. In the embodiment shown, the COTsharing information of each of the CG-UCIs 338, 340, and 342 identifiesthe downlink transmission opportunity 336 by including an indication 1of a time delay (or offset) from the transmission of the CG-UCI to thebeginning of the downlink transmission opportunity 336 and an indicationd of a duration of the downlink transmission opportunity 336, althoughalternative embodiments may differ.

In the embodiment shown, the indication l indicates a number of timeslots from the time slot of the CG-UCI to the time slot of the beginningof the downlink transmission opportunity, and may be referred to as anindication of an offset from the transmission of the CG-UCI to thebeginning of the downlink transmission opportunity 336. However,alternative embodiments may differ. For example, alternative embodimentsmay indicate a time delay (or offset) to a beginning of a downlinktransmission opportunity other than by indicating a number of time slotsand other than by indicating a time from transmission of the CG-UCI.

Further, in the embodiment shown, the indication d indicates a number oftime slots of the downlink transmission opportunity. However,alternative embodiments may differ and may, for example, indicate aduration of a downlink transmission opportunity other than a number oftime slots of the downlink transmission opportunity.

In some embodiments, the COT sharing information of a CG-UCI may includean identifier of a combination in an ordered set of combinations of (l,d). In general, ordered sets of combinations of (l, d) as describedherein may be configured or predefined. An identifier of a combinationin an ordered set of combinations of (l, d) identifies the l and the dof the combination and therefore identifies both the time delay from thetransmission of the CG-UCI to the beginning of the downlink transmissionopportunity, and the duration of the downlink transmission opportunity.In this example, the CG-UCI 338 may include a combination index value(CIV) or other identifier identifying the combination (l=2, d=2) in anordered set of combinations of (l, d), and the CG-UCIs 340 and 342 mayeach include a CIV or other identifier identifying the combination (l=1,d=2) in the ordered set of combinations of (l, d).

This example includes three CG-UCIs 338, 340, and 342, which may avoidambiguity if the base station 170 a fails to detect some of the CG-UCIs.However, alternative embodiments may include more or fewer CG-UCIs.However, in alternative embodiments, some of the CG-UCIs included in theUL burst may indicate combinations of (l, d) that correspond to anotherforthcoming DL transmission opportunity, for example when multiple DLtransmission opportunities are not consecutive in time and the UE mayresume the CG UL transmission between the DL transmission opportunities.

In the embodiment shown, after the uplink burst 334 from the UE 110 a tothe base station 170 a, the base station 170 a initiates a downlinktransmission 344 from the base station 170 a to the UE 110 a in thedownlink transmission opportunity 336 after a downlink (DL) LBTprocedure 346 at the beginning of the time slot 306. To accommodate theDL LBT procedure 346, and to accommodate other LBT procedures thatswitch from an uplink transmission to a downlink transmission, the basestation 170 a may blank one or more downlink symbols based on thenumerology or SCS of the active BWP to provide a switching gap betweenthe uplink transmission and the downlink transmission.

In other words, in response to the COT sharing information of one, morethan one, or all of the CG-UCIs 338, 340, and 342, the base station 170a transmits, and the UE 110 a receives, the downlink transmission 344 inthe downlink transmission opportunity 336 identified by the COT sharinginformation of the CG-UCIs 338, 340, and 342. Therefore, the COT sharinginformation of one, more than one, or all of the CG-UCIs 338, 340, and342 allow the base station 170 a to share the COT in the MCOT 318 bytransmitting the downlink transmission 344 to the UE 110 a in thedownlink transmission opportunity 336 identified by the COT sharinginformation of the CG-UCIs 338, 340, and 342.

In the embodiment shown, the DL LBT procedure 346 is a category 2 (CAT2)DL LBT procedure, which does not involve a random back-off, but inalternative embodiments, the base station may initiate a downlinktransmission using other procedures such as CAT1 (no LBT) procedure, forinstance when the gap between UL and DL is 16 μs or less. In thisexample, the DL LBT procedure 346 was successful, and the downlinktransmission 344 includes a first physical downlink shared channel(PDSCH) 348 in the time slot 306 and a second PDSCH 350 in the time slot308. In this embodiment, and in some other embodiments, timing of thedownlink transmission 344 is chosen such that the time slot 306 in whichthe downlink transmission 344 begins includes a physical downlinkcontrol channel (PDCCH) 352, but alternative embodiments may differ.

In this example, the downlink transmission 344 is within the timeresource 300 and within the MCOT 318. However, in alternativeembodiments, a downlink transmission may extend beyond a time resourceas described herein.

In this example, the UE 110 a attempts to resume uplink transmission inthe COT of the MCOT 318 by a third UL LBT procedure 354 before the endof the time slot 308. To accommodate the UL LBT procedure 354, and toaccommodate other LBT procedures that switch from a downlinktransmission to an uplink transmission, the base station 170 a may blankone or more downlink symbols based on the numerology or SCS of theactive BWP to provide a switching gap between the downlink transmissionand the uplink transmission.

In the embodiment shown, the third UL LBT procedure 354 is a CAT2 UL LBTprocedure, but in alternative embodiments, a UE may attempt to resumeuplink transmission using other procedures. In this example, the thirdUL LBT procedure 354 was successful, and the UE 110 a resumes uplinktransmission in the COT of the MCOT 318 by transmitting a PUSCH 356 inthe time slot 310. The PUSCH 356 includes a CG-UCI 358, and the COTsharing information of the CG-UCI 358 includes a “disabling” indicationindicating no downlink transmission opportunity thereafter.

FIG. 4 illustrates another example of a time resource 400 for configuredgrant by the UE 110 a in an unlicensed spectrum in the cell 175 a of thebase station 170 a according to one embodiment, although alternativeembodiments may involve different UEs, different cells, and/or differentbase stations.

In the example of FIG. 4 , the time resource 400 includes five timeslots 402, 404, 406, 408, and 410, and the UE 110 a attempted toinitiate COT for an uplink transmission to the base station 170 a in thetime resource 400 by an UL LBT procedure 412 at the beginning of thetime slot 402. In this example, the UL LBT procedure 412 was successful,and the UE 110 a initiated COT having a MCOT 414 of four time slots inthe time slots 402, 404, 406, and 408 in the time resource 400. Duringthe COT in the MCOT 414, the UE 110 a transmits an uplink transmissionto the base station 170 a in a PUSCH 416 in the time slot 402, in aPUSCH 418 in the time slot 402, in a PUSCH 420 in the time slot 404, andin a PUSCH 422 in the time slot 404. The PUSCHs 416, 418, 420, and 422therefore form an uplink burst 424 in an uplink transmission from the UE110 a to the base station 170 a in the time resource 400 in theunlicensed spectrum in the cell 175 a of the base station 170 a.

However, in this example, the uplink burst 424 does not extend into thetime slots 406 and 408 that are within the MCOT 414. Therefore, theuplink burst 424 includes indications of a downlink transmissionopportunity 426 (or, more generally, a transmission opportunity) in thetime slots 406 and 408 during the COT in the MCOT 414. The downlinktransmission opportunity 426 begins two time slots after the time slot402, begins one time slot after the time slot 404, and has a duration oftwo time slots 406 and 408.

In this example, at the time of the PUSCH 416, the UE 110 a may not haveidentified an end of the uplink burst 424 in the time slot 404 andtherefore may not have identified a beginning of the downlinktransmission opportunity 426 in the time slot 406. Therefore, in thisexample, the PUSCH 416 in the time slot 402 includes a CG-UCI 428, andthe COT sharing information of the CG-UCI 428 includes a “disabling”indication indicating no downlink transmission opportunity, similar tothe COT sharing information of the CG-UCI 358 shown in FIG. 3 .

However, in this example, at the time of the PUSCH 418, the UE 110 a hasidentified the end of the uplink burst 424 in the time slot 404 and hasidentified the beginning of the downlink transmission opportunity 426 inthe time slot 406. Therefore, in this example, the PUSCH 418 includes aCG-UCI 430, and the COT sharing information of the CG-UCI 430 includesan indication that the downlink transmission opportunity 426 begins twotime slots after the time slot 402, indicated by l=2 in FIG. 4 . The COTsharing information of the CG-UCI 430 also includes an indication thatthe downlink transmission opportunity 426 has a duration of two timeslots, indicated by d=2 in FIG. 4 . The COT sharing information of theCG-UCI 430 may therefore be similar to the COT sharing information ofthe COT sharing information of the CG-UCI 338 shown in FIG. 3 . Further,in this example, the PUSCH 420 includes a CG-UCI 432, and the COTsharing information of the CG-UCI 432 may be similar to the COT sharinginformation of the CG-UCI 340 shown in FIG. 3 . Further, in thisexample, the PUSCH 422 includes a CG-UCI 434, and the COT sharinginformation of the CG-UCI 434 may be similar to the COT sharinginformation of the CG-UCI 342 shown in FIG. 3 . Again, the values of land d in the embodiment of FIG. 4 are examples only, and alternativeembodiments may include different indications of a time delay (oroffset) to a beginning of a downlink transmission opportunity, andalternative embodiments may include different indications of a durationof the downlink transmission opportunity.

In the embodiment shown, after the uplink burst 424 from the UE 110 a tothe base station 170 a, the base station 170 a initiates a downlinktransmission 436 from the base station 170 a to the UE 110 a in thedownlink transmission opportunity 426 after a DL LBT procedure 438 atthe beginning of the time slot 406. The DL LBT procedure 438 may besimilar to the DL LBT procedure 346 shown in FIG. 3 , and the downlinktransmission 436 may be similar to the downlink transmission 344 shownin FIG. 3 , although alternative embodiments may differ.

Indications of Offsets and Durations

In a configured-grant time resource, a MCOT of COT initiated by a UE hasN_(p,μ) time slots, where p represents the channel access priority class(CAPC) used to initiate the COT and μ represents a numerology of theconfigured-grant time resource. For example, in some embodiments inwhich μ=1(30 kHz), N_(1,1)=4, N_(2,1)=8, N_(3,1)=12, and N_(4,1)=12,although alternative embodiments may differ.

In the embodiments of FIGS. 3 and 4 , when COT sharing information of aCG-UCI indicates that l=0, the COT sharing information of the CG-UCIindicates a downlink transmission opportunity beginning in a same timeslot as transmission of the CG-UCI. A downlink transmission in a sametime slot as transmission of a CG-UCI may be described as a partial-slotdownlink transmission. Also, in the embodiments of FIGS. 3 and 4 , whena CG-UCI is in the first time slot of a MCOT and indicates that adownlink transmission opportunity begins in the last time slot of theMCOT, the CG-UCI indicates that 1=N_(p,μ)−1. Therefore, in theembodiments of FIGS. 3 and 4 , values of 1 may range from 0 toN_(p,μ)−1.

Further, in some embodiments, d=0 or another indicator may indicate apartial-slot downlink opportunity (as described below with reference toFIG. 9 ), and d=N_(p,μ)−1 indicates a downlink opportunity in all of theremaining time slots of the MCOT after the first slot that may or maynot have a partial DL transmission. Therefore, in some embodiments,values of d may range from 0 to N_(p,μ)−1. Further, to maintain thedownlink opportunity within the MCOT,

-   -   l+d<N_(p,μ).

Therefore, the number of combinations of (l, d) that could be used isthe number of combinations of (l, d) that satisfy 0≤l≤N_(p,μ)−1,0≤N_(p,μ)−1, and l+d<N_(p,μ), which is

$C_{p,\mu} = {\frac{N_{p,\mu}\left( {N_{p,\mu} + 1} \right)}{2}.}$

The C_(p,μ) combinations of (l, d) may be ordered in an ordered set ofcombinations of (l, d), and combinations in the ordered set ofcombinations of (l, d) may be identified by values of an index.Therefore, a value of an index may identify a combination in an orderedset of combinations of (l, d), and the value of an index thereforeidentifies the time delay, represented by the combination, fromtransmission of a CG-UCI to a beginning of a downlink transmissionopportunity, and the value of an index also identifies the duration,represented by the combination, of the downlink transmissionopportunity.

In the embodiments of FIGS. 3 and 4 , each of the CG-UCIs 338, 340, 342,358, 428, 430, 432, and 434 includes COT sharing information in additionto any other data in the CG-UCIs, and the COT sharing informationincludes either a “disabling” indication indicating no downlinktransmission opportunity or an identifier of a combination in an orderedset of combinations of (l, d). Therefore, the number of possible values(or possible index values) of the COT sharing information of each of theCG-UCIs 338, 340, 342, 358, 428, 430, 432, and 434 for a particular pand for a particular μ is 1+C_(p,μ), and the number of bits required forthe COT sharing information of each of the CG-UCIs is

$B_{p,\mu} = {\left\lceil {1 + {\log_{2}\left( C_{p,\mu} \right)}} \right\rceil = {\left\lceil {1 + {\log_{2}\left( \frac{N_{p,\mu}\left( {N_{p,\mu} + 1} \right)}{2} \right)}} \right\rceil.}}$

In other words, in the embodiments of FIGS. 3 and 4 , for a particular pand for a particular μ, each of the CG-UCIs 338, 340, 342, 358, 428,430, 432, and 434 may include COT sharing information encoded in atleast B_(p,μ) bits, and the bits in the COT sharing information of theCG-UCIs may indicate an index value representing either a “disabling”indication indicating no downlink transmission opportunity or anidentifier of a combination in an ordered set of combinations of (l, d).However, CG-UCIs according to other embodiments may differ as describedbelow, for example.

Indications of CAPC

In the embodiments of FIGS. 3 and 4 and some other embodiments,different configured-grant resources may be used for particularrespective CAPCs.

However, in some other embodiments, configured-grant resources may beused for more than one CAPC. When configured-grant resources may be usedfor more than one CAPC, COT sharing information in a CG-UCI may includean indicator of a CAPC p that the UE used to initiate the COT. Forexample, in some embodiments, COT sharing information of a CG-UCI mayinclude two bits, a different number of bits, or a different indicatorto indicate a CAPC p that the UE used to initiate the COT.

Index Values Indicating CAPC, Offset, and Duration

For a particular numerology represented by p, an index value identifiedin COT sharing information of a CG-UCI may be a number encoded in BMbits and ranging from 0 to 2^(B) ^(μ) −1. In some embodiments, an indexvalue identified in COT sharing information of a CG-UCI may identifyboth a CAPC p that the UE used to initiate the COT and an identifier ofa combination in an ordered set of combinations of (l, d) as shown inthe following example. In the following example, p=0 indicates a“disabling” indication, and for convenient reference, Δ_(p,μ) is definedas

Δ_(p,μ)=Σ_(i=0) ^(p) C _(i,μ)

with C _(0,μ)=1.

CIV Range Start CIV Range End CAPC p CIV Identifies 0 0 0 “Disabling”indication indicating no downlink transmission opportunity C_(0, μ) = 1C_(1, μ) 1 One of C_(1, μ) combinations of (l, d) Δ_(1, μ) = C_(1, μ) +1 C_(1, μ) + C_(2, μ) 2 One of C_(2, μ) combinations of (l, d) Δ_(2, μ)= Δ_(1, μ) + C_(2, μ) C_(1, μ) + C_(2, μ) + C_(3, μ) 3 One of C_(3, μ)combinations of (l, d) Δ_(3, μ) = Δ_(2, μ) + C_(3, μ) C_(1, μ) +C_(2, μ) + 4 One of C_(4, μ) combinations of (l, d) C_(3, μ) + C_(4, μ)Δ_(4, μ) = Δ_(3, μ) + C_(4, μ) 2^(B) ^(μ) − 1 None Reserved (if any)

In other words, in this example, an index value of 0 indicates a“disabling” indication indicating no downlink transmission opportunity,an index value from 1 to C_(1,μ) indicates a respective combination ofan ordered set of C₁, combinations of (l, d), an index value fromΔ_(1,μ) to C_(1,μ)+C_(2,μ) indicates a respective combination of anordered set of C_(2,μ) combinations of (l, d), and so on. In thisexample, p ranges from 0 to 4, so Δ_(4,μ) CIV values are required.Therefore, the number of bits required to indicate the number C ofrequired CIV values (where C is a number of combinations configured, andC=Δ_(4,μ) in this example) is B_(μ)=┌log₂C┐, and any index values from Cto 2^(B) ^(μ) −1 are unused, or reserved.

Again, alternative embodiments may differ. For example, in alternativeembodiments, one or more index values or other indicators may indicate aCAPC p that the UE used to initiate the COT, a “disabling” indicationindicating no downlink transmission opportunity, a time delay (oroffset) to a beginning of a downlink transmission opportunity, aduration of the downlink transmission opportunity, or a combination oftwo or more thereof.

Indications of Offsets within a Time Slot Including a “UL Burst End” Bit

FIG. 5 illustrates an example of a time resource 500 for configuredgrant by the UE 110 a in an unlicensed spectrum in the cell 175 a of thebase station 170 a according to one embodiment, although alternativeembodiments may involve different UEs, different cells, and/or differentbase stations.

In the example of FIG. 5 , the time resource 500 includes five timeslots 502, 504, 506, 508, and 510, and the UE 110 a attempted toinitiate COT for an uplink transmission to the base station 170 a in thetime resource 500 by a first UL LBT procedure 512 at the beginning ofthe time slot 502. In this example, the first UL LBT procedure 512failed because of a “busy” assessment. The UE 110 a attempted again toinitiate COT for an uplink transmission to the base station 170 a in thetime resource 500 by proceeding with a second UL LBT procedure 516towards the next potential PUSCH starting point, which is after a delay514 from the beginning of the time slot 502. In the embodiment shown,the first UL LBT procedure 512 and the second UL LBT procedure 516 areCAT₄ UL LBT procedures, but in alternative embodiments, a UE may attemptto initiate COT using other procedures.

In this example, the second UL LBT procedure 516 was successful, and theUE 110 a initiated COT having a MCOT 518 of four time slots 520, 522,524, and 526 in the time resource 500. The COT in the MCOT 518 istherefore COT initiated by the UE 110 a. During the COT in the MCOT 518,the UE 110 a transmits an uplink transmission to the base station 170 ain a PUSCH 528 in the time slot 502 and in a PUSCH 530 in the time slot504. The PUSCHs 528 and 530 therefore form an uplink burst 532 in anuplink transmission from the UE 110 a to the base station 170 a in thetime resource 500 in the unlicensed spectrum in the cell 175 a of thebase station 170 a.

However, in this example, the uplink burst 532 does not occupy theentire time slot 504, and the uplink burst 532 does not extend into thetime slots 506 and 508 that are within the MCOT 518. Therefore, theuplink burst 532 includes indications of a downlink transmissionopportunity 534 (or, more generally, a transmission opportunity) duringthe COT in the MCOT 518. The downlink transmission opportunity 534includes a partial-slot portion 536 of the downlink transmissionopportunity 534 in a portion of the time slot 504 that is not occupiedby the uplink burst 532. The downlink transmission opportunity 534 alsoincludes a portion 538 of the downlink transmission opportunity 534 inthe time slots 506 and 508. The downlink transmission opportunity 534begins one time slot after the time slot 502, and begins in the sametime slot 504 as the PUSCH 530. Further, the portion 538 of the downlinktransmission opportunity 534, which is the portion of the downlinktransmission opportunity 534 that begins after the time slot 504 of thePUSCH 530, has a duration of two time slots 506 and 508 as indicated byd=2 in FIG. 5 . In other words, the downlink transmission opportunity534 has a duration of two time slots, as indicated by d=2 in FIG. 5 , inaddition to the partial-slot portion 536, which is the portion of thedownlink transmission opportunity 534 in the same time slot 504 as thePUSCH 530.

In this example, the PUSCH 528 in the time slot 502 includes a CG-UCI540, and the COT sharing information of the CG-UCI 540 includes anindication that the downlink transmission opportunity 534 begins onetime slot after the time slot 502, again indicated by l=1 in FIG. 5 .The COT sharing information of the CG-UCI 540 also includes anindication that the downlink transmission opportunity 534 has a durationof two time slots, again indicated by d=2 in FIG. 5 , in addition to thepartial-slot portion 536 of the downlink transmission opportunity 534 inthe same time slot 504 as the PUSCH 530. The COT sharing information ofthe CG-UCI 540 may therefore be similar to the COT sharing informationof the of CG-UCI 340 or of the CG-UCI 342 as shown in FIG. 3 , exceptthat the CG-UCI 540 also includes a “UL burst end” bit 542.

As indicated above, the COT sharing information of each of the CG-UCIs340 and 342 may each include a CIV or other identifier identifying thecombination (l=1, d=2) in an ordered set of combinations of (l, d), andthe COT sharing information of the CG-UCI 540 may also include a CIV orother identifier identifying the combination (l=1, d=2) in the orderedset of combinations of (l, d). However, in the embodiment shown, inaddition to the identifier of the combination (l=1, d=2) in the orderedset of combinations of (l, d), the COT sharing information of the CG-UCI540 also includes the “UL burst end” bit 542 indicating, with a bitvalue of ‘o’ in this example, that the PUSCH 528 is not the end of theuplink burst 532.

In this example, the PUSCH 530 in the time slot 504 includes a CG-UCI544, and the COT sharing information of the CG-UCI 544 includes anindication that the downlink transmission opportunity 534 begins with apartial slot in the same time slot 504 as the CG-UCI 544, indicated bythe DL offset l=0 in FIG. 5 . The COT sharing information of the CG-UCI544 also includes an indication that the downlink transmissionopportunity 534 has a duration of two time slots, again indicated by d=2in FIG. 5 , in addition to the partial-slot portion 536 of the downlinktransmission opportunity 534 in the same time slot 504 as the PUSCH 530.Therefore, in the embodiment shown, the COT sharing information of theCG-UCI 544 includes a CIV or other identifier identifying thecombination (l=0, d=2) in an ordered set of combinations of (l, d), andin addition to the identifier of the combination (l=0, d=2) in theordered set of combinations of (l, d), the CG-UCI 544 also includes a“UL burst end” bit 546 indicating, with a bit value of ‘1’ in thisexample, that the PUSCH 530 is the end of the uplink burst 532. In otherwords, the “UL burst end” bit 546 is an indication that the beginning ofthe downlink transmission opportunity 534 is in the same time slot 504of the COT in the MCOT 518 as the transmission of the CG-UCI 544, the“UL burst end” bit 546 is an indication that the beginning of thedownlink transmission opportunity 534 is in a same time slot of the COTas an end of an uplink burst including the transmission of the CG-UCI544, and the “UL burst end” bit 546 is an indication of a time (in thisexample, the time being after the PUSCH 530 including the CG-UCI 544) ofthe beginning of the downlink transmission opportunity 534 within thesame time slot 504 as the transmission of the CG-UCI 544.

Again, in the embodiment of FIG. 5 , the values of l and d, and the “ULburst end” bits 542 and 546, are examples only. Alternative embodimentsmay include different indications of a time delay (or offset) to abeginning of a downlink transmission opportunity. Alternativeembodiments may also include different indications of a duration of thedownlink transmission opportunity. Alternative embodiments may alsoinclude different indications of whether a downlink transmissionopportunity is in a same time slot of the COT as transmission of CG-UCI.Alternative embodiments may also include different indications of an endof an uplink burst.

In the embodiment shown, after the uplink burst 532 from the UE 110 a tothe base station 170 a, the base station 170 a initiates a downlinktransmission 548 from the base station 170 a to the UE 110 a in thedownlink transmission opportunity 532 by a downlink DL LBT procedure 550after the PUSCH 530 and in the time slot 504. In the embodiment shown,the DL LBT procedure 550 is a CAT2 DL LBT procedure, which does notinvolve a random back-off, but in alternative embodiments, base stationmay initiate a downlink transmission using other procedures. In thisexample, the DL LBT procedure 550 was successful, and the downlinktransmission 548 includes a first PDSCH 552 in the time slot 504, asecond PDSCH 554 in the time slot 506, and a third PDSCH 556 in the timeslot 508, although alternative embodiments may differ.

In this example, an idle period 558 of at least 100 μs follows thedownlink transmission 548, and after the idle period 558, the UE 110 aattempts to resume uplink transmission in the COT of the MCOT 518 by athird UL LBT procedure 560 before the end of the time slot 508. In theembodiment shown, the third UL LBT procedure 560 is a CAT2 UL LBTprocedure, but in alternative embodiments, a UE may attempt to resumeuplink transmission using other procedures. In this example, the thirdUL LBT procedure 560 was successful, and the UE 110 a resumes uplinktransmission in the COT of the MCOT 518 by transmitting a PUSCH 562 inthe time slot 510. The PUSCH 562 includes a CG-UCI 564, and the COTsharing information of the CG-UCI 564 includes a “disabling” indicationthat may be similar to the “disabling” indication of the CG-UCI 358.Further, in the embodiment shown, in addition to the “disabling”indication, the COT sharing information of the CG-UCI 564 includes a “ULburst end” bit 566 indicating, with a bit value of ‘1’ in this example,that the PUSCH 562 is the end of an uplink burst including the PUSCH562.

In the embodiment of FIG. 5 , each of the time slots 502, 504, 506, 508,and 510 includes no more than two PUSCHs, and the PUSCH 530 is the onlyPUSCH in the time slot 504. Therefore, in the embodiment of FIG. 5 , ifthe downlink transmission opportunity 534 begins in the time slot 504,then the time slot 504 has no capacity for another PUSCH after the PUSCH530, and the indication that l=0 in the COT sharing information of theCG-UCI 544 of the PUSCH 530, which indicates that the downlinktransmission opportunity 534 begins in the same time slot as the CG-UCI,also implies that the uplink burst 532 will end after the PUSCH 530 andthat the downlink transmission opportunity 534 begins after the PUSCH530. As a result, in the embodiment of FIG. 5 —and in other embodimentsin which an indication, in COT sharing information of a CG-UCI of aPUSCH, that a downlink transmission opportunity begins in a same timeslot as a CG-UCI implies that the downlink transmission opportunity 534begins after the PUSCH—the “UL burst end” may not require a separate bitand may be omitted.

FIG. 6 illustrates an alternative to the embodiment of FIG. 5 . In theembodiment of FIG. 6 , a time resource for configured grant by the UE110 a in an unlicensed spectrum in the cell 175 a of the base station170 a includes time slots 602, 604, and 606 in COT initiated by the UE110 a and within a MCOT of the COT, although alternative embodiments mayinvolve different UEs, different cells, and/or different base stations.

In the example of FIG. 6 , during an uplink burst 608 in an uplinktransmission from the UE 110 a to the base station 170 a in a timeresource in the unlicensed spectrum in the cell 175 a of the basestation 170 a, the UE 110 a transmits an uplink transmission to the basestation 170 a in a PUSCH 610 in the time slot 602 and in a PUSCH 612 inthe time slot 602.

Again, in this example, the uplink burst 608 does not occupy the entiretime slot 602, and the uplink burst 608 does not extend into the timeslots 604 and 606 that are also within the MCOT. Therefore, the uplinkburst 608 includes indications of a downlink transmission opportunity614 (or, more generally, a transmission opportunity). A partial-slotportion of the downlink transmission opportunity 614 is in a portion ofthe time slot 602 that is not occupied by the uplink burst 606. Anotherportion of the downlink transmission opportunity 614 is in the timeslots 604 and 606. Therefore, the downlink transmission opportunity 614begins in the same time slot 602 as the PUSCHs 610 and 612. Further, theportion of the downlink transmission opportunity 614 that begins afterthe time slot 602 has a duration of two time slots 604 and 606. In otherwords, the downlink transmission opportunity 614 has a duration of twotime slots in addition to the partial-slot portion of the downlinktransmission opportunity 614 in the same time slot 602 as the PUSCHs 610and 612.

In this example, the PUSCH 610 in the time slot 602 includes a CG-UCI616, and the COT sharing information of the CG-UCI 616 includes anindication that the downlink transmission opportunity 614 begins in thesame time slot 602 as the CG-UCI 616, indicated by l=0 in FIG. 6 . TheCOT sharing information of the CG-UCI 616 also includes an indicationthat the downlink transmission opportunity 614 has a duration of twotime slots, indicated by d=2 in FIG. 6 , in addition to the partial-slotportion of the downlink transmission opportunity 614 in the same timeslot 602 as the PUSCHs 610 and 612. Therefore, in the embodiment shown,the COT sharing information of the CG-UCI 616 includes a CIV or otheridentifier identifying the combination (l=0, d=2) in an ordered set ofcombinations of (l, d). Further, in addition to the identifier of thecombination (l=0, d=2) in the ordered set of combinations of (l, d), theCG-UCI 616 also includes a “UL burst end” bit 618 indicating, with a bitvalue of ‘0’ in this example, that the PUSCH 610 is not the end of theuplink burst 608.

Further, in this example, the PUSCH 612 in the time slot 602 includes aCG-UCI 620, and the COT sharing information of the CG-UCI 620 includesan indication that the downlink transmission opportunity 614 begins inthe same time slot 602 as the CG-UCI 620, indicated by the DL offset l=0in FIG. 6 . The COT sharing information of the CG-UCI 616 also includesan indication that the downlink transmission opportunity 614 has aduration of two time slots, indicated by d=2 in FIG. 6 , in addition tothe partial-slot portion of the downlink transmission opportunity 614 inthe same time slot 602 as the PUSCHs 610 and 612. Therefore, in theembodiment shown, the COT sharing information of the CG-UCI 616 includesa CIV or other identifier identifying the combination (l=0, d=2) in anordered set of combinations of (l, d). Further, in addition to theidentifier of the combination (l=0, d=2) in the ordered set ofcombinations of (l, d), the CG-UCI 616 also includes a “UL burst end”bit 622 indicating, with a bit value of ‘1’ in this example, that thePUSCH 612 is the end of the uplink burst 608. In other words, the “ULburst end” bit 622 is an indication that the beginning of the downlinktransmission opportunity 614 is in the same time slot 602 of the COT inthe MCOT as the transmission of the CG-UCI 622, the “UL burst end” bit622 is an indication that the beginning of the downlink transmissionopportunity 614 is in a same time slot of the COT as an end of an uplinkburst including the transmission of the CG-UCI 622, and the “UL burstend” bit 622 is an indication of a time (in this example, the time beingafter the PUSCH 612 including the CG-UCI 622) of the beginning of thedownlink transmission opportunity 614.

The example of FIG. 6 may then continue with a downlink transmission inthe downlink transmission opportunity from the base station 170 a to theUE 110 a in the downlink transmission opportunity 614 as described abovewith reference to FIG. 5 , for example.

However, unlike the embodiment of FIG. 5 , in the embodiment of FIG. 6 ,the time slot 602 may include, and does include, more than one PUSCH inaddition to the partial-slot portion of the downlink transmissionopportunity 614 in the same time slot 602 as the PUSCHs 610 and 612.Therefore, unlike the embodiment of FIG. 5 , the indication that l=0 inthe COT sharing information of the CG-UCI 616 of the PUSCH 610 does notnecessarily imply that the uplink burst 608 will end after the PUSCH 610or that the downlink transmission opportunity 614 begins after the PUSCH610. As a result, unlike the embodiment of FIG. 5 , in the embodiment ofFIG. 6 —and in some other embodiments in which an indication, in COTsharing information of a CG-UCI of a PUSCH, that a downlink transmissionopportunity begins in a same time slot as a CG-UCI does not necessarilyimply that the downlink transmission opportunity 534 begins after thePUSCH—the “UL burst end” or an alternative to the “UL burst end” may berequired.

Therefore, in the embodiment of FIG. 6 , for a particular p and for aparticular P, each of the CG-UCIs 616 and 620 includes COT sharinginformation in addition to any other data in the CG-UCIs, and the COTsharing information includes either an identifier of a combination in anordered set of combinations of (l, d) or a “disabling” indicationindicating no downlink transmission opportunity, and the COT sharinginformation of each of the CG-UCIs 616 and 620 also includes a “UL burstend” bit. Therefore, in the embodiments of FIG. 6 , for a particular pand for a particular p, the number of bits required for the COT sharinginformation of each of the CG-UCIs 616 and 620 is

$B_{p,\mu} = {{\left\lceil {\log_{2}\left( {C_{p,\mu} + 1} \right)} \right\rceil + 1} = {\left\lceil {\log_{2}\left( {\frac{N_{p,\mu}\left( {N_{p,\mu} + 1} \right)}{2} + 1} \right)} \right\rceil + {1.}}}$

However, CG-UCIs according to other embodiments may differ. For example,in some embodiments, a UE may blank one or more downlink symbols basedon the numerology or SCS of the active BWP after the end of the lastPUSCH of an uplink burst to create a switching gap between the uplinkburst and a subsequent downlink transmission, and the “UL burst end” ofa CG-UCI may be two or more bits to indicate a beginning of a downlinktransmission opportunity for the subsequent downlink transmission afterthe one or more blanked downlink symbols. Still other CG-UCIs accordingto other embodiments are described below.

Index Values Including Indications of Offsets within a Time Slot

As indicated above, the “UL burst end” bit 546 or 622 in the COT sharinginformation of a CG-UCI indicates a time of a beginning of a downlinktransmission opportunity within a same time slot as the transmission ofthe CG-UCI and indicates the time of the beginning of the downlinktransmission opportunity in a same time slot of the COT as an end of anuplink burst including the transmission of the CG-UCI. However, as alsoindicated above, the “UL burst end” bits require at least one additionalbit in each of the CG-UCIs 616 and 620.

In some embodiments, the CG-UCI may indicate an index value that mayindicate a beginning of a downlink transmission opportunity within asame time slot as the transmission of the CG-UCI, or in a same time slotof the COT as an end of an uplink burst including the transmission ofthe CG-UCI, without necessarily requiring an additional “UL burst end”bit as in the embodiment of FIG. 6 .

FIG. 7 illustrates an example of a time resource 700 for configuredgrant by the UE 110 a in an unlicensed spectrum in the cell 175 a of thebase station 170 a according to one embodiment, although alternativeembodiments may involve different UEs, different cells, and/or differentbase stations.

In the example of FIG. 7 , the time resource 700 includes five timeslots 702, 704, 706, 708, and 710, and the UE 110 a initiated a COThaving a MCOT 712 of four time slots in the time resource 700. Duringthe COT in the MCOT 712, the UE 110 a transmits an uplink transmissionto the base station 170 a in a PUSCH 714 in the time slot 702, in aPUSCH 716 in the time slot 702, in a PUSCH 718 in the time slot 704, andin a PUSCH 720 in the time slot 704. The PUSCHs 714, 716, 718, and 720therefore form an uplink burst 722 in an uplink transmission from the UE110 a to the base station 170 a in the time resource 700 in theunlicensed spectrum in the cell 175 a of the base station 170 a.

However, in this example, the uplink burst 722 does not occupy theentire time slot 704, and the uplink burst 722 does not extend into thetime slots 706 and 708 that are within the MCOT 712. Therefore, theuplink burst 722 includes indications of a downlink transmissionopportunity 724 (or, more generally, a transmission opportunity) duringthe COT in the MCOT 712. A partial-slot portion of the downlinktransmission opportunity 724 is in a portion of the time slot 704 thatis not occupied by the uplink burst 722. Another portion of the downlinktransmission opportunity 724 is in the time slots 706 and 708.Therefore, the downlink transmission opportunity 724 begins in the sametime slot 704 as the PUSCHs 718 and 720. Further, the portion of thedownlink transmission opportunity 724 that begins after the time slot704 has a duration of two time slots 706 and 708. In other words, thedownlink transmission opportunity 724 has a duration of two time slotsin addition to the partial-slot portion of the downlink transmissionopportunity 724 in the same time slot 704 as the PUSCHs 718 and 720.

In this example, the PUSCH 714 in the time slot 702 includes a CG-UCI726, and the PUSCH 716 in the time slot 702 includes a CG-UCI 728. TheCOT sharing information of the CG-UCIs 726 and 728 each includes anindication that the downlink transmission opportunity 724 begins onetime slot after the time slot 702, and indications that the downlinktransmission opportunity 702 has a duration of two time slots inaddition to the partial-slot portion of the downlink transmissionopportunity 724 in the same time slot 704 as the PUSCHs 718 and 720. TheCOT sharing information of the CG-UCIs 726 and 728 may therefore besimilar to the COT sharing information of the CG-UCIs 340 or 342 asshown in FIG. 3 .

Further, in this example, the PUSCH 718 in the time slot 704 includes aCG-UCI 730, and the COT sharing information of the CG-UCI 730 includesan indication that the downlink transmission opportunity 724 begins inthe same time slot 704 as the CG-UCI 730, indicated by the DL offset l=0in FIG. 7 . The CG-UCI 730 also includes an indication that the downlinktransmission opportunity 724 has a duration of two time slots, againindicated by d=2 in FIG. 7 , in addition to the partial-slot portion ofthe downlink transmission opportunity 724 in the same time slot 704 asthe PUSCHs 718 and 720. Therefore, in the embodiment shown, the COTsharing information of the CG-UCI 730 includes a CIV or other identifieridentifying the combination (l=0, d=2) in an ordered set of combinationsof (l, d).

In this example, the slot 704 includes 14 symbols, the PUSCH 718occupied the first four symbols of the slot 704, and the PUSCH 720occupied the first three symbols of the slot 704. Therefore, in thisexample, the PUSCH 720 in the time slot 704 includes a CG-UCI 732, andthe COT sharing information of the CG-UCI 732 includes an indicationthat a beginning of the downlink transmission opportunity 724 is afterthe first seven symbols in the time slot 704, indicated by “UL burst endOS #6” in FIG. 7 , and the COT sharing information of the CG-UCI 732includes an indication of a ending symbol of the UL burst 722.

Therefore, in some embodiments, the COT sharing information of theCG-UCI 732 includes an indication of an uplink burst end symbol numberN_(ULE) indicating a symbol in the time slot 704 before the beginning ofthe downlink transmission opportunity 724. In this example, the slot 704includes 14 symbols, and at least one PUSCH occupies at least twosymbols of the slot 704. Therefore, in this example, the slot 704 has upto 14−2=12 symbols (from OS #1 to OS #11) when the downlink transmissionopportunity 724 could begin in the next OS. In general, the number ofsymbols in a slot when a uplink burst could end may be referred to as anumber of uplink burst endpoints N_(ULBEP).

In an alternative embodiment, rather than indicating an uplink burst endsymbol number N_(ULE), sharing information of a CG-UCI may indicate aPUSCH that is the last PUSCH of an uplink burst that ends in a time slothaving a partial-slot downlink opportunity. For example, if a time slotincludes 14 symbols, and if a PUSCH has a length of at least twosymbols, then the time slot may include up to seven PUSCHs. In thatexample, if an uplink burst ends during the time slot and the time slotincludes a partial-slot downlink opportunity, then the time slot mayinclude up to six PUSCHs, and an indicator of a number from the set {0,1, . . . , 5} may indicate which PUSCH in the time slot is the lastPUSCH of the uplink burst. Such an indicator of a last PUSCH of anuplink burst may therefore, in addition to or alternatively to otherindicators such as those described herein, indicate a symbol of abeginning of a downlink transmission opportunity.

As indicated above, in some embodiments, an index value identified byCOT sharing information of a CG-UCI may identify both a CAPC p that theUE used to initiate the COT and an identifier of a combination in anordered set of combinations of (l, d). However, in the embodiment ofFIG. 7 , for example, an index value identified by COT sharinginformation of a CG-UCI may identify either both a CAPC p that the UEused to initiate the COT and an identifier of a combination in anordered set of combinations of (l, d) or a time of the beginning of thedownlink transmission opportunity in the same time slot of the COT asthe transmission of the CG-UCI, as shown in the following example.

CIV Range Start CIV Range End CAPC p CIV Identifies 0 0 0 “Disabling”indication indicating no downlink transmission opportunity C_(0, μ) = 1C_(1, μ) 1 One of C_(1, μ) combinations of (l, d) Δ_(1, μ) = C_(1, μ) +1 C_(1, μ) + C_(2, μ) 2 One of C_(2, μ) combinations of (l, d) Δ_(2, μ)= Δ_(1, μ)+ C_(2, μ) C_(1, μ) + C_(2, μ) + C_(3, μ) 3 One of C_(3, μ)combinations of (l, d) Δ_(3, μ) = Δ_(2, μ) + C_(3, μ) C_(1, μ) +C_(2, μ) + 4 One of C_(4, μ) combinations of (l, d) C_(3, μ) + C_(4, μ)Δ_(4, μ) = Δ_(3, μ) + C_(4, μ) Δ_(4, μ) + N_(ULBEP) − 1 None An uplinkend symbol number N_(ULE) of N_(ULBEP) uplink burst endpoints Δ_(4, μ) +N_(ULBEP) 2^(B) ^(μ) − 1 None Reserved (if any)

In this example, an index value from Δ_(4,μ) to Δ_(4,μ)+N_(ULBEP)indicates an uplink symbol number N_(ULE) of the N_(ULBEP) uplink burstendpoints, so Δ_(4,μ)+N_(ULBEP) CIV values are required, the number ofbits required to indicate the number of required CIV values is 2^(B)^(μ) =┌log₂ (Δ_(4,μ)+N_(ULBEP))┐, and any index values fromΔ_(4,μ)+N_(ULBEP)+1 to 2^(B) ^(μ) −1 are unused, or reserved.

An example of index values is shown below in an embodiment in which μ=1(30 kHz), N_(1,1)=4, N_(2,1)=8, N_(3,1)=12, N_(4,1)=12, N_(ULBEP)=11,B₁=8 bits in addition to any bits that may be required for other data inthe CG-UCIs, and 2^(B) ¹ =256.

CIV Range Start CIV Range End CAPC p CIV Identifies 0 0 0 “Disabling”indication indicating no downlink transmission opportunity C_(0,1) = 1C_(1,1) = 10 1 $\begin{matrix}{{{One}{of}C_{1,\mu}} = {\frac{N_{1,1}\left( {N_{1,1} + 1} \right)}{2} =}} \\{\frac{4 \times 5}{2} = {10{combinations}{of}\left( {l,d} \right)}}\end{matrix}$ Δ_(1,1) = C_(1,1) + 1 = 11 C_(1,1) + C_(2,1) = 46 2$\begin{matrix}{{{One}{of}C_{2,\mu}} = {\frac{N_{2,1}\left( {N_{2,1} + 1} \right)}{2} =}} \\{\frac{8 \times 9}{2} = {36{combinations}{of}\left( {l,d} \right)}}\end{matrix}$ Δ_(2,1) = Δ_(1,1) + C_(2,1) = 47 C_(1,1) + C_(2,1) +C_(3,1) = 124 3 $\begin{matrix}{{{One}{of}C_{3,\mu}} = {\frac{N_{3,1}\left( {N_{3,1} + 1} \right)}{2} =}} \\{\frac{12 \times 13}{2} = {78{combinations}{of}\left( {l,d} \right)}}\end{matrix}$ Δ_(3,1) = Δ_(2,1) + C_(3,1) = 125 C_(1,1) + C_(2,1) +C_(3,1) + C_(4,1) = 202 4 $\begin{matrix}{{{One}{of}C_{4,\mu}} = {\frac{N_{4,1}\left( {N_{4,1} + 1} \right)}{2} =}} \\{\frac{12 \times 13}{2} = {78{combinations}{of}\left( {l,d} \right)}}\end{matrix}$ Δ_(4,1) = Δ_(3,1) + C_(4,1) = 203 Δ_(4,1) + N_(ULBEP) − 1= 213 None An uplink end symbol number N_(ULE) of N_(ULBEP) = 11 uplinkburst endpoints Δ_(4,1) + N_(ULBEP) = 214 2^(B) ¹ − 1 = 255 NoneReserved

In this example, in which p∈{1, 2, 3, 4}, a CIV identifying acombination (l, d) may be identified by

${{CIV}\left( {l,d} \right)} = \left\{ {\begin{matrix}{{N_{p,\mu}d} + l + \Delta_{{p - 1},\mu}} & {{{if}d} \leq \left\lfloor \frac{N_{p,\mu}}{2} \right\rfloor} \\{{N_{p,\mu}\left( {N_{p,\mu} - d} \right)} + \left( {N_{p,\mu} - l - 1} \right) + \Delta_{{p - 1},\mu}} & {otherwise}\end{matrix}.} \right.$

Again, in this example in which p∈{1, 2, 3, 4}, a CIV identifying anuplink end symbol number N_(ULE)∈{1, 2, . . . , N_(ULBEP)} may beidentified by

CIV(N _(ULE))=N _(ULE)+Δ_(4,μ)−1.

In this example in which p∈{1, 2, 3, 4}, a CIV may be decoded asfollows.

If CIV=0, then CIV indicates a “disabling” indication indicating nodownlink transmission opportunity.

If CIV≥Δ_(4,μ), then CIV indicates N_(ULE)=CIV−Δ_(4,μ)+1.

If 0≤CIV<Δ_(4,μ), then for p that satisfies Δ_(p-1,μ)≤CIV<Δ_(p,μ), CIVindicates

$d = \left\{ {\begin{matrix}\left\lfloor \frac{CIV}{N_{p,\mu}} \right\rfloor & {{{if}\left\lfloor \frac{CIV}{N_{p,\mu}} \right\rfloor} \leq \left\lfloor \frac{N_{p,\mu}}{2} \right\rfloor} \\{N_{p,\mu} - \left\lfloor \frac{CIV}{N_{p,\mu}} \right\rfloor} & {otherwise}\end{matrix}{and}} \right.$ $l = \left\{ {\begin{matrix}{{CIV} - {N_{p,\mu}d}} & {{{if}\left\lfloor \frac{CIV}{N_{p,\mu}} \right\rfloor} \leq \left\lfloor \frac{N_{p,\mu}}{2} \right\rfloor} \\{N_{p,\mu} - {CIV} - 1 + {N_{p,\mu}\left( {N_{p,\mu} - d} \right)}} & {otherwise}\end{matrix}.} \right.$

In this example, the CIV indicating respective combinations (l, d) forp=1 are as follows.

d C_(0,μ) + 0 1 2 3 l 0 0 4 8 7 1 1 5 9 2 2 6 3 3

In this example, the CIV indicating respective combinations (l, d) forp=2 are as follows.

d Δ_(1,μ)+ 0 1 2 3 4 5 6 7 l 0 0 8 16 24 32 31 23 15 1 1 9 17 25 33 3022 2 2 10 18 26 34 29 3 3 11 19 27 35 4 4 12 20 28 5 5 13 21 6 6 14 7 7

In this example, the CIV indicating respective combinations (l, d) forp=3 are as follows.

d Δ_(2,μ)+ 0 1 2 3 4 5 6 7 8 9 10 11 l 0 0 12 24 36 48 60 72 71 59 47 3523 1 1 13 25 37 49 61 73 70 58 46 34 2 2 14 26 38 50 62 74 69 57 45 3 315 27 39 51 63 75 68 56 4 4 16 28 40 52 64 76 67 5 5 17 29 41 53 65 77 66 18 30 42 54 66 7 7 19 31 43 55 8 8 20 32 44 9 9 21 33 10 10 22 11 11

In this example, the CIV indicating respective combinations (l, d) forp=4 are as follows.

d Δ_(3,μ)+ 0 1 2 3 4 5 6 7 8 9 10 11 l 0 0 12 24 36 48 60 72 71 59 47 3523 1 1 13 25 37 49 61 73 70 58 46 34 2 2 14 26 38 50 62 74 69 57 45 3 315 27 39 51 63 75 68 56 4 4 16 28 40 52 64 76 67 5 5 17 29 41 53 65 77 66 18 30 42 54 66 7 7 19 31 43 55 8 8 20 32 44 9 9 21 33 10 10 22 11 11

In the example of FIG. 7 , the COT sharing information of the CG-UCI 730includes an indication that the downlink transmission opportunity 724has a duration of two time slots in addition to the partial-slot portionof the downlink transmission opportunity 724 in the same time slot 704as the PUSCHs 718 and 720, indicated by d=2 in FIG. 7 , and the COTsharing information of the CG-UCI 732 includes an indication that abeginning of the downlink transmission opportunity 724 is after thefirst seven symbols in the time slot 704, indicated by “UL burst end OS#6” in FIG. 7 . In the example of FIG. 7 , a duration of the downlinktransmission opportunity 724 is a number of downlink symbols

N _(SDL)=(N _(SS) −N _(ULE)−₁)+d·N _(SS)

where N_(SS) is a number of symbols in each time slot. Therefore, in theexample of FIG. 7 , the CG-UCIs 730 and 732 collectively includeindications of a duration of the downlink transmission opportunity 724and of the beginning of the downlink transmission opportunity 724.

Again, alternative embodiments may differ. For example, in alternativeembodiments, one or more index values or other indicators may indicate aCAPC p that the UE used to initiate the COT, a “disabling” indicationindicating no downlink transmission opportunity, a time delay (oroffset) to a beginning of a downlink transmission opportunity, aduration of the downlink transmission opportunity, a time of thebeginning of the downlink transmission opportunity in the same time slotas the transmission of the CG-UCI, or a combination of two or morethereof. In some other embodiments, the order of transmitting the COTsharing information of the CG-UCIs 730 and 732 may be reversed withoutimpacting the collective COT sharing information indicated to the basestation 170 a.

After the PUSCH 720 as described above, the example of FIG. 7 may thencontinue with a downlink transmission in the downlink transmissionopportunity from the base station 170 a to the UE 110 a in the downlinktransmission opportunity 614 as described above with reference to FIG. 5, for example.

FIG. 8 illustrates an example of a time resource 800 for configuredgrant by the UE 110 a in an unlicensed spectrum in the cell 175 a of thebase station 170 a according to one embodiment, although alternativeembodiments may involve different UEs, different cells, and/or differentbase stations.

In the example of FIG. 8 , the time resource 800 includes five timeslots 802, 804, 806, 808, and 810, and the UE 110 a initiated a COThaving a MCOT 812 of four time slots in the time resource 800. Duringthe COT in the MCOT 812, the UE 110 a transmits an uplink transmissionto the base station 170 a in a PUSCH 814 in the time slot 802 and in aPUSCH 816 in the time slot 804. The PUSCHs 814 and 816 therefore form anuplink burst 818 in an uplink transmission from the UE 110 a to the basestation 170 a in the time resource 800 in the unlicensed spectrum in thecell 175 a of the base station 170 a.

In this example, the PUSCH 814 in the time slot 802 includes a CG-UCI820, and the PUSCH 816 in the time slot 804 includes a CG-UCI 822.Similar to the COT sharing information of the CG-UCI 732, the COTsharing information of the CG-UCI 820 includes an indication that abeginning of a downlink transmission opportunity 824 (or, moregenerally, a transmission opportunity) is after the first seven symbols,indicated by “UL burst end OS #6” in FIG. 8 . The CG-UCI 820 is in thetime slot 802, and the first six symbols of the time slot 802 havealready passed, so the CG-UCI 820 indicates instead that the beginningof the downlink transmission opportunity 824 is after the first sevensymbols of the next time slot, namely the time slot 804, or moregenerally, after the first seven symbols of a subsequent slot in the ULburst. The COT sharing information of the CG-UCI 822 includes anindication of the DL offset (l=0) and thus confirms that the beginningof the downlink transmission opportunity 824 is after the first sevensymbols of the same time slot, namely the time slot 804. The COT sharinginformation of the CG-UCI 822 further includes an indication of theduration (indicated by d=2 in FIG. 8 ) of the downlink transmissionopportunity 824.

In summary, in the example of FIG. 8 , the CG-UCI 820, which includesthe indication of the beginning of the downlink transmission opportunity824, may be in the PUSCH 814 before the PUSCH 816, which is the lastPUSCH of the an uplink burst 818 and the last PUSCH before the beginningof the downlink transmission opportunity 824. Therefore, the indicationof the beginning of the downlink transmission opportunity 824 in the COTsharing information of the CG-UCI 820 is an indication that thebeginning of the downlink transmission opportunity 824 is in a same timeslot of the COT as an end of an uplink burst including the transmissionof the CG-UCI 820, and the indication of the beginning of the downlinktransmission opportunity 824 in the COT sharing information of theCG-UCI 820 is an indication of a time (in this example, the time beingafter the first seven symbols of the next time slot, namely the timeslot 804) of the beginning of the downlink transmission opportunity 824.

COT Sharing Information Payload Size

In some embodiments, a base station may configure a UE to use a bitfield having a configured payload size of B_(p,μ) bits for COT sharinginformation in CG-UCIs in addition to any bits that may be required forother data in the CG-UCIs.

As indicated above, in the embodiments of FIGS. 3 and 4 and some otherembodiments, different configured-grant resources may be used forparticular respective CAPCs, and B_(p,μ) may be determined without anybits to indicate the CAPC p that the UE used to initiate the COT.

However, as also indicated above, COT sharing information of a CG-UCImay include two bits, or a different number of bits, to indicate a CAPCp that the UE used to initiate the COT, and B_(p,μ) may be determined toinclude any bits that indicate the CAPC p that the UE used to initiatethe COT.

In other embodiments, an index value may indicate a CAPC p that the UEused to initiate the COT, in which case B_(p,μ) may be determinedwithout any bits to indicate the CAPC p that the UE used to initiate theCOT.

In general, in some embodiments, B_(p,μ) may be determined toaccommodate the largest possible p, such as B_(4,μ) for example,irrespective of the actual CAPC p that the UE used to initiate the COT,to avoid a variable size of the CG-UCI.

As indicated above, a MCOT of COT initiated by a UE has N_(p,μ) timeslots. In some embodiments, a configured payload size B_(p,μ) may bedetermined as the number of bits required for all CIV values that may berequired. The number of CIV values that may be required may bedetermined according to one of the examples above, or in other ways. Insome embodiments, when determining the number of CIV values that may berequired, N_(p,μ) may be based on the numerology or SCS μ of an activeBWP, or may be based on a reference numerology or SCSμ_(ref)=0 (15 kHz,for example) irrespective of the numerology or SCS of the active BWP.

When N_(p,μ) is based on a reference numerology or SCSμ_(ref), and whenμ>μ_(ref), indications of time delay 1 and indications of duration drepresent more than one time slot and therefore have coarser granularitythan when N_(p,μ) is based on a numerology or SCSμ of an active BWP.

Therefore, when N_(p,μ) is based on a reference numerology orSCSp_(ref), when μ>μ_(ref), and when a CIV value indicates a duration dof a downlink transmission opportunity, the actual duration of thedownlink transmission opportunity in the numerology or SCSμ of an activeBWP may be longer than the duration indicated by d, and the base stationmay transmit a downlink transmission having a duration of d×2^(μ-μ)^(ref) time slots, in addition to a partial-slot DL transmission ifindicated.

However, when N_(p,μ) is based on a reference numerology or SCSμ_(ref),and when μ>μ_(ref), the COT sharing information may require anadditional slot offset adjustment value j to indicate a slot time delayin a number of slots. For example, when μ−μ_(ref)=1, one bit in the COTsharing information may represent j such that j∈{0, 1}, and 1 andj maycollectively indicate a time delay (or offset) of l×2^(μ-μ) ^(ref)+j=2l+j time slots. As another example, when μ−μ_(ref)=2, two bits inthe COT sharing information may represent j such that j∈{0, 1, 2, 3},and l and j may collectively indicate a time delay (or offset) ofl×2^(μ-μ) ^(ref) +j=4l+j time slots. Therefore, in some embodiments,μ−μ_(ref) bits in the COT sharing information may represent j.Furthermore, in another example, when μ≤μ_(ref), no bits in the COTsharing information may be configured for the CG-UCI transmitted in theBWP configured with the numerology or SCSμ.

Partial-Slot Downlink Opportunities

As indicated above, in some embodiments, d=0 or another indicator mayindicate a partial-slot downlink opportunity. For example, FIG. 9illustrates a time resource 900 according to one embodiment forconfigured grant by the UE 110 a in an unlicensed spectrum in the cell175 a of the base station 170 a according to one embodiment, althoughalternative embodiments may involve different UEs, different cells,and/or different base stations.

In the example of FIG. 9 , the time resource 900 includes four timeslots 902, 904, 906, and 908, and the UE 110 a initiated a COT having aMCOT 910 of the same four time slots 902, 904, 906, and 908 in the timeresource 900. During the COT in the MCOT 910, the UE 110 a transmits anuplink transmission to the base station 170 a in a PUSCH 912 in the timeslot 902, in a PUSCH 914 in the time slot 902, and in a PUSCH 916 in thetime slot 904. The PUSCHs 912, 914, and 916 therefore form an uplinkburst 918 in an uplink transmission from the UE 110 a to the basestation 170 a in the time resource 900 in the unlicensed spectrum in thecell 175 a of the base station 170 a.

In the embodiment shown, after the uplink burst 918 from the UE 110 a tothe base station 170 a, the base station 170 a initiates a downlinktransmission including a PDSCH 920 in the time slot 904 by a downlink DLLBT procedure 922. To accommodate the DL LBT procedure 922, the basestation 170 a may blank one or more downlink symbols based on thenumerology or SCS of the active BWP and a CP extension not exceeding onesymbol duration to provide a switching gap between the uplinktransmission and the downlink transmission. The switching gap betweenthe uplink burst 918 and the PDSCH 920 may be 16 μs or 25 μs if the DLLBT procedure 922 is a CAT2 DL LBT procedure. Alternatively, theswitching gap between the uplink burst 918 and the PDSCH 920 may be 16μs if the DL LBT procedure 922 is a category 1 (CAT1) LBT, i.e., directtransmission without LBT performed in the switching gap.

In this example, the UE 110 a resumes uplink transmission in the COT ofthe MCOT 910 after a gap 924 of at least 100 μs from the PDSCH 920 tothe first PUSCH 926 of the resumed uplink transmission. The resumeduplink transmission may be resumed by a CAT2 UL LBT procedure 928 in aswitching gap, which may be 25 μs, for example. However, in otherembodiments, the UE 110 a may resume uplink transmission according toone or more uplink grants that may have been received in the PDCCH 921included in the downlink transmission including the PDSCH 920. Suchuplink grants may indicate an LBT type and a switching gap duration forresuming the uplink transmission.

Multiple Active Configurations

FIG. 10 illustrates an example of a time resource 1000 for configuredgrant by the UE 110 a in an unlicensed spectrum in the cell 175 a of thebase station 170 a according to one embodiment, although alternativeembodiments may involve different UEs, different cells, and/or differentbase stations.

In the example of FIG. 10 , the UE 110 a attempted to initiate COT foran uplink transmission to the base station 170 a in the time resource1000 by a first UL LBT procedure 1002 and later by a second UL LBTprocedure 1004. The UL LBT procedures 1002 and 1004 failed. After the ULLBT procedures 1002 and 1004, the UE 110 a attempted to initiate COT foran uplink transmission to the base station 170 a in the time resource1000 by a third UL LBT procedure 1006, and the third UL LBT procedure1006 succeeded. Therefore, following UL LBT procedure 1006, the UE 110 ainitiated COT in the time resource 1000.

In this example, at the time of the UL LBT procedures 1002, 1004, and1006, the time resource 1000 had three (indicated by n=3 in FIG. 10 )short four-symbol (indicated by L=4 in FIG. 10 ) mini-slot CG PUSCHs pertime slot, and one mini-slot CG PUSCH per four-symbol mini-slot.However, after the UE 110 a initiated the COT in the time resource 1000,the UE 110 a switched to another configured-grant configuration, whichmay be a default configuration, including two seven-symbol slots pertime slot, and one 14-symbol PUSCH per slot. The embodiment of FIG. 10is an example only, and in alternative embodiments, a UE may switchbetween two or more different configured-grant configurations that maydiffer from the two configured-grant configurations that are shown inFIG. 10 .

In some embodiments, a UE may be configured with a hybrid configurationincluding parameters for different configured-grant configurations. Forexample, in some embodiments, to avoid control overhead, a UE may beconfigured with a CG-UCI payload size accounting for COT sharinginformation for only CG-PUSCHs of a default configuration. In otherembodiments, a UE may be configured with a first CG-UCI payload sizeaccounting for a first COT sharing information for a defaultconfiguration, and may be configured with a second smaller CG-UCIpayload size accounting for a second COT sharing information forCG-PUSCHs of an initial configuration by reducing N_(p,μ) or eliminatingsome combinations of (l, d) to reflect shorter mini-slots per time slot.

In some other embodiments, if the CG time-domain resource configurationindicates that CG-PUSCHs of different length can be transmitted inaccordance with the same configuration, e.g., in the same slot as inFIG. 7 (PUSCH 718 and 720), or across different slots as in the hybridconfiguration discussed above, the CG-UCI payload size including the COTsharing information size, along with the resource mapping beta offsetvalue, may be determined based on the CG PUSCH of the smallest size,whereas rate matching may be used by the UE to map the CG-UCI payloadbits to the larger resources on the larger CG PUSCHs as determined bythe beta offset value.

Sidelink Transmissions

The foregoing examples illustrate sharing of COT for downlinktransmissions. However, in other embodiments, COT may be shared insidelink transmissions between two UEs, such as the UEs 110 a and 110 b,for example. Sharing of COT in sidelink transmissions may be similar tosharing of COT for downlink transmissions as described above, exceptthat sharing of COT in sidelink transmissions would involve sharing COTin sidelink configured grant, rather than sharing COT in configuredgrant from a base station. The sidelink configured grant resources maybe determined by the base station or may be selected from a configuredresource pool by the COT transmitting UE initiating the COT.

DL Transmit Power Level and Energy Detection Threshold

In embodiments such as those described herein, the base station may beusing a higher transmit power level than that of the UE that initiatedthe UL COT. In order to improve the coexistence fairness with othernodes/radio access technologies operating in the same unlicensedspectrum, the base station may apply one or more of the followingtechniques:

The base station may reduce its CCA energy detection threshold. The CCAis part of the DL LBT procedure the base station uses to access the DLtransmission opportunity indicated via the COT sharing information inthe CG-UCI.

The base station may reduce its transmission power level to match thetransmit power level of the UE that initiated the UL COT. The basestation may predict the transmit power of the UE using the ULmeasurements such as SRS measurements and/or by tracking the transmitpower control (TPC) commands it sent to the UE.

Other Examples

This disclosure includes the following other examples as furtherillustrations of embodiments of the disclosure, which are not intendedto limit the scope of the disclosure.

1. A method performed by a user equipment (UE) for configured-granttransmission, the method comprising:

-   -   transmitting, by the UE, a configured-grant uplink control        information (CG-UCI) to a base station during a channel        occupancy time (COT) in an unlicensed spectrum, the CG-UCI        comprising an indication of a time delay to a beginning of a        downlink transmission opportunity during the COT; and    -   receiving, by the UE, a downlink transmission within the        downlink transmission opportunity.        2. The method of example 1 wherein the CG-UCI further comprises        an indication of a duration of the downlink transmission        opportunity.        3. The method of example 2 wherein the indication of the        duration indicates, at least, a number of time slots of the        downlink transmission opportunity.        4. The method of example 2 or 3 wherein the CG-UCI comprises a        value of an index, the value of the index comprising the        indication of the time delay and the indication of the duration.        5. The method of example 4, wherein the value of the index        indicates, at least, a combination in an ordered set of        combinations of:    -   time delays to the beginning of the downlink transmission        opportunity; and durations of the downlink transmission        opportunity.        6. The method of any one of examples 1 to 5 wherein the        indication of the time delay indicates, at least, a number of        time slots of the COT from transmission of the CG-UCI to the        beginning of the downlink transmission opportunity.        7. The method of any one of examples 1 to 5 wherein the        indication of the time delay indicates, at least, that the        beginning of the downlink transmission opportunity is in a same        time slot of the COT as an end of an uplink burst comprising the        transmission of the CG-UCI.        8. The method of example 7 wherein the indication of the time        delay indicates, at least, that the beginning of the downlink        transmission opportunity is in a same time slot of the COT as        the transmission of the CG-UCI.        9. The method of example 7 or 8 wherein the indication of the        time delay comprises a value of at least one bit in the CG-UCI        indicating an end of the uplink burst comprising the        transmission of the CG-UCI.        10. The method of example 1 wherein:    -   the indication of the time delay comprises a value of an index,        the value of the index comprising the indication of the time        delay; and    -   some other values of the index identify respective combinations        in an ordered set of combinations of:    -   time delays to the beginning of the downlink transmission        opportunity; and    -   durations of the downlink transmission opportunity.        11. The method of any one of examples 1 to 10 wherein the        indication of the time delay indicates, at least, a symbol of        the beginning of the downlink transmission opportunity.        12. The method of any one of examples 1 to 11 wherein receiving        the downlink transmission comprises receiving the downlink        transmission from the base station.        13. The method of any one of examples 1 to 12 wherein receiving        the downlink transmission comprises receiving the downlink        transmission in at least one physical downlink shared channel        (PDSCH).        14. The method of any one of examples 1 to 13 wherein        transmitting the CG-UCI to the base station comprises        transmitting a physical uplink shared channel (PUSCH) comprising        the CG-UCI.        15. The method of any one of examples 1 to 14 wherein the COT        was initiated by the UE.        16. The method of example 15 wherein the COT was initiated by        the UE in a channel access priority class (CAPC), and wherein        the CG-UCI further comprises an indication of the CAPC.        17. A user equipment (UE) apparatus comprising:    -   at least one processor; and    -   at least one processor-readable storage device comprising stored        thereon processor-executable instructions that, when executed by        the at least one processor, cause the at least one processor to,        at least:    -   execute a method according to any one of examples 1 to 16.        18. A method performed by a base station for configured-grant        transmission, the method comprising:    -   receiving, by the base station, a configured-grant uplink        control information (CG-UCI) from a user equipment (UE) during a        channel occupancy time (COT) in an unlicensed spectrum, the        CG-UCI comprising an indication of a time delay to a beginning        of a downlink transmission opportunity during the COT; and    -   transmitting, by the base station, a downlink transmission to        the UE within the downlink transmission opportunity.        19. The method of example 18 wherein the CG-UCI further        comprises an indication of a duration of the downlink        transmission opportunity.        20. The method of example 19 wherein the indication of the        duration indicates, at least, a number of time slots of the        downlink transmission opportunity.        21. The method of example 19 or 20 wherein the CG-UCI comprises        a value of an index, the value of the index comprising the        indication of the time delay and the indication of the duration.        22. The method of example 21, wherein the value of the index        indicates, at least, a combination in an ordered set of        combinations of:    -   time delays to the beginning of the downlink transmission        opportunity; and durations of the downlink transmission        opportunity.        23. The method of any one of examples 18 to 22 wherein the        indication of the time delay indicates, at least, a number of        time slots of the COT from transmission of the CG-UCI to the        beginning of the downlink transmission opportunity.        24. The method of any one of examples 18 to 22 wherein the        indication of the time delay indicates, at least, that the        beginning of the downlink transmission opportunity is in a same        time slot of the COT as an end of an uplink burst comprising the        transmission of the CG-UCI.        25. The method of example 24 wherein the indication of the time        delay indicates, at least, that the beginning of the downlink        transmission opportunity is in a same time slot of the COT as        the transmission of the CG-UCI.        26. The method of example 24 or 25 wherein the indication of the        time delay comprises a value of at least one bit in the CG-UCI        indicating an end of the uplink burst comprising the        transmission of the CG-UCI.        27. The method of example 18 wherein:    -   the indication of the time delay comprises a value of an index,        the value of the index comprising the indication of the time        delay; and    -   some other values of the index identify respective combinations        in an ordered set of combinations of:    -   time delays to the beginning of the downlink transmission        opportunity; and    -   durations of the downlink transmission opportunity.        28. The method of any one of examples 18 to 27 wherein the        indication of the time delay indicates, at least, a symbol of        the beginning of the downlink transmission opportunity.        29. The method of any one of examples 18 to 28 wherein        transmitting the downlink transmission comprises transmitting        the downlink transmission in at least one physical downlink        shared channel (PDSCH).        30. The method of any one of examples 18 to 29 wherein receiving        the CG-UCI comprises receiving a physical uplink shared channel        (PUSCH) comprising the CG-UCI.        31. The method of any one of examples 18 to 30 wherein the COT        was initiated by the UE.        32. The method of example 31 wherein the COT was initiated by        the UE in a channel access priority class (CAPC), and wherein        the CG-UCI further comprises an indication of the CAPC.        33. A base station apparatus comprising:    -   at least one processor; and    -   at least one processor-readable storage device comprising stored        thereon processor-executable instructions that, when executed by        the at least one processor, cause the at least one processor to,        at least:    -   execute a method according to any one of examples 18 to 32.

Discussion of Disclosed Embodiments

In embodiments such as those described herein, a UE may flexiblyindicate a time delay (or offset) to a beginning of a downlinktransmission opportunity during COT, and a duration of the downlinktransmission opportunity. The beginning and the duration of the downlinktransmission opportunity may be identified for different reasons, suchas allowing a switching gap as may be appropriate between an uplinktransmission and a subsequent downlink transmission, or between adownlink transmission and a subsequent uplink transmission.

COT sharing information may encode an indication of a time delay (oroffset) to a beginning of a downlink transmission, a duration of thedownlink transmission opportunity, a CAPC that a UE used to initiate theCOT, or a combination of two or more thereof using a CIV or otherindications such as those described above, for example.

Embodiments such as those described above may facilitate multipleswitching points, for example uplink-downlink-uplink oruplink-downlink-uplink-downlink.

In general, embodiments such as those described above may makerelatively efficient use of available resources when compared to othermethods and apparatuses.

Although specific embodiments have been described and illustrated, suchembodiments should be considered illustrative only and not as limitingthe invention as construed according to the accompanying claims.

What is claimed is:
 1. A method comprising: transmitting, by a userequipment (UE) to a base station, a configured-grant uplink controlinformation (CG-UCI) during a channel occupancy time (COT) initiated bythe UE in a shared spectrum, the CG-UCI comprising COT sharinginformation, the COT sharing information indicating, at least, an indexvalue corresponding to a combination of: an indication of an offset to abeginning of a downlink transmission opportunity during the COT, and anindication of a duration of the downlink transmission opportunity duringthe COT, wherein the index value corresponds to a row of a configuredtable of COT sharing combinations, the row corresponding to thecombination, and at least one row of the configured table of COT sharingcombinations indicates that COT sharing is not available; and receiving,by the UE from the base station, a downlink transmission within thedownlink transmission opportunity and in accordance with the COT sharinginformation in the CG-UCI.
 2. The method of claim 1, wherein theindication of the duration indicates, at least, a number of time slotsof the downlink transmission opportunity.
 3. The method of claim 2,wherein the indication of the duration has a maximum value of N−1,wherein N is a number of slots in a maximum duration (MCOT) of the COTinitiated by the UE based on at least a subcarrier spacing of aconfigured grant resource.
 4. The method of claim 1, wherein theindication of the offset indicates, at least, a number of time slots ofthe COT from transmission of the CG-UCI to the beginning of the downlinktransmission opportunity.
 5. The method of claim 4, wherein theindication of the offset has a maximum value of N−1 wherein N is anumber of slots in a maximum duration (MCOT) of the COT initiated by theUE based on at least a subcarrier spacing of a configured grantresource.
 6. The method of claim 1, wherein the index value correspondsto the row of the configured table of COT sharing combinations, the rowcorresponding to the combination, and wherein a bitwidth of the COTsharing information in the CG-UCI is ┌log₂C┐bits, wherein C is a numberof combinations configured in the configured table.
 7. The method ofclaim 1, further comprising: after the transmitting the CG-UCI to thebase station and before the beginning of the downlink transmissionopportunity, transmitting, by the UE to the base station, at least onesubsequent CG-UCI during the COT, wherein each subsequent CG-UCI of theat least one subsequent CG-UCI comprises subsequent COT sharinginformation indicating, at least, the downlink transmission opportunity.8. A method comprising: receiving, by a base station from a userequipment (UE), a configured-grant uplink control information (CG-UCI)during a channel occupancy time (COT) initiated by the UE in a sharedspectrum, the CG-UCI comprising COT sharing information, the COT sharinginformation indicating, at least, an index value corresponding to acombination of: an indication of an offset to a beginning of a downlinktransmission opportunity during the COT, and an indication of a durationof the downlink transmission opportunity during the COT, wherein theindex value corresponds to a row of a configured table of COT sharingcombinations, the row corresponding to the combination, and at least onerow of the configured table of COT sharing combinations indicates thatCOT sharing is not available; and transmitting, by the base station tothe UE, a downlink transmission within the downlink transmissionopportunity and in accordance with the COT sharing information in theCG-UCI.
 9. The method of claim 8, wherein the indication of the durationindicates, at least, a number of time slots of the downlink transmissionopportunity.
 10. The method of claim 9, wherein the indication of theduration has a maximum value of N−1, wherein N is a number of slots in amaximum duration (MCOT) of the COT initiated by the UE based on at leasta subcarrier spacing of a configured grant resource.
 11. The method ofclaim 8, wherein the indication of the offset indicates, at least, anumber of time slots of the COT from transmission of the CG-UCI to thebeginning of the downlink transmission opportunity.
 12. The method ofclaim 11, wherein the indication of the offset has a maximum value ofN−1, wherein N is a number of slots in a maximum duration (MCOT) of theCOT initiated by the UE based on at least a subcarrier spacing of aconfigured grant resource.
 13. The method of claim 8, wherein the indexvalue corresponds to the row of the configured table of COT sharingcombinations, the row corresponding to the combination, and wherein abitwidth of the COT sharing information in the CG-UCI is ┌log₂C┐bits,wherein C is a number of combinations configured in the configuredtable.
 14. The method of claim 8, further comprising: after thereceiving the CG-UCI from the UE and before the beginning of thedownlink transmission opportunity, receiving, by the base station fromthe UE, at least one subsequent CG-UCI during the COT, wherein eachsubsequent CG-UCI of the at least one subsequent CG-UCI comprisessubsequent COT sharing information indicating, at least, the downlinktransmission opportunity.
 15. An apparatus comprising: at least oneprocessor; and a non-transitory computer readable storage medium storingprogramming, the programming including instructions that, when executedby the at least one processor, cause the apparatus to perform:transmitting, to a base station, a configured-grant uplink controlinformation (CG-UCI) during a channel occupancy time (COT) initiated bythe apparatus in a shared spectrum, the CG-UCI comprising COT sharinginformation, the COT sharing information indicating, at least, an indexvalue corresponding to a combination of: an indication of an offset to abeginning of a downlink transmission opportunity during the COT, and anindication of a duration of the downlink transmission opportunity duringthe COT, wherein the index value corresponds to a row of a configuredtable of COT sharing combinations, the row corresponding to thecombination, and at least one row of the configured table of COT sharingcombinations indicates that COT sharing is not available; and receiving,from the base station, a downlink transmission within the downlinktransmission opportunity and in accordance with the COT sharinginformation in the CG-UCI.
 16. The apparatus of claim 15, wherein theindication of the duration indicates, at least, a number of time slotsof the downlink transmission opportunity.
 17. The apparatus of claim 16,wherein the indication of the duration has a maximum value of N−1,wherein N is a number of slots in a maximum duration (MCOT) of the COTinitiated by the apparatus based on at least a subcarrier spacing of aconfigured grant resource.
 18. The apparatus of claim 15, wherein theindication of the offset indicates, at least, a number of time slots ofthe COT from transmission of the CG-UCI to the beginning of the downlinktransmission opportunity.
 19. The apparatus of claim 18, wherein theindication of the offset has a maximum value of N−1 wherein N is anumber of slots in a maximum duration (MCOT) of the COT initiated by theapparatus based on at least a subcarrier spacing of a configured grantresource.
 20. The apparatus of claim 15, wherein the index valuecorresponds to the row of the configured table of COT sharingcombinations, the row corresponding to the combination, and wherein abitwidth of the COT sharing information in the CG-UCI is ┌log₂C┐bits,wherein C is a number of combinations configured in the configuredtable.
 21. The apparatus of claim 15, further comprising: after thetransmitting the CG-UCI to the base station and before the beginning ofthe downlink transmission opportunity, transmitting, to the basestation, at least one subsequent CG-UCI during the COT, wherein eachsubsequent CG-UCI of the at least one subsequent CG-UCI comprisessubsequent COT sharing information indicating, at least, the downlinktransmission opportunity.
 22. An apparatus comprising: at least oneprocessor; and a non-transitory computer readable storage medium storingprogramming, the programming including instructions that, when executedby the at least one processor, cause the apparatus to perform:receiving, from a user equipment (UE), a configured-grant uplink controlinformation (CG-UCI) during a channel occupancy time (COT) initiated bythe UE in a shared spectrum, the CG-UCI comprising COT sharinginformation, the COT sharing information indicating, at least, an indexvalue corresponding to a combination of: an indication of an offset to abeginning of a downlink transmission opportunity during the COT, and anindication of a duration of the downlink transmission opportunity duringthe COT, wherein the index value corresponds to a row of a configuredtable of COT sharing combinations, the row corresponding to thecombination, and at least one row of the configured table of COT sharingcombinations indicates that COT sharing is not available; andtransmitting, to the UE, a downlink transmission within the downlinktransmission opportunity and in accordance with the COT sharinginformation in the CG-UCI.
 23. The apparatus of claim 22, wherein theindication of the duration indicates, at least, a number of time slotsof the downlink transmission opportunity.
 24. The apparatus of claim 23,wherein the indication of the duration has a maximum value of N−1,wherein N is a number of slots in a maximum duration (MCOT) of the COTinitiated by the UE based on at least a subcarrier spacing of aconfigured grant resource.
 25. The apparatus of claim 22, wherein theindication of the offset indicates, at least, a number of time slots ofthe COT from transmission of the CG-UCI to the beginning of the downlinktransmission opportunity.
 26. The apparatus of claim 25, wherein theindication of the offset has a maximum value of N−1, wherein N is anumber of slots in a maximum duration (MCOT) of the COT initiated by theUE based on at least a subcarrier spacing of a configured grantresource.
 27. The apparatus of claim 22, wherein the index valuecorresponds to the row of the configured table of COT sharingcombinations, the row corresponding to the combination, and wherein abitwidth of the COT sharing information in the CG-UCI is ┌log₂C┐bits,wherein C is a number of combinations configured in the configuredtable.
 28. The apparatus of claim 22, further comprising: after thereceiving the CG-UCI from the UE and before the beginning of thedownlink transmission opportunity, receiving, from the UE, at least onesubsequent CG-UCI during the COT, wherein each subsequent CG-UCI of theat least one subsequent CG-UCI comprises subsequent COT sharinginformation indicating, at least, the downlink transmission opportunity.